Update, Nov 17/09: Upon my last visit to Montreal, I found out that Cruella is back where it was, and Diabolik and Rock Montreal have just traded which sides of the street they are on. There is also a costume store in the area with the largest selection of tights and stockings I've ever seen. 
I've been meaning to write this for awhile but thought I'd finally get around to it now. I know a number of those reading this journal are going to Montreal for Kinetik, so I have some recommendations to share re: getting around, based on my having lived in Montreal a few years back.
This entry will not make much sense unless you have a metro map. And you will be wanting the metro, as driving in Montreal tends to be a pain in the ass. Accordingly, everywhere I discuss here you can either get to on the metro or via bus 55 which goes north/south on rue Saint-Laurent and stops at the Saint-Laurent metro.
First of all, hotels: there are a bunch of cheap-but-acceptable ones on rue Saint-Denis near Berri metro. (Berri is the metro where three lines cross.) I've stayed at several and while you do have to bring your own shampoo/soap/etc., otherwise they are fine for somewhere that you are only going to sleep at anyway. Plus the advantage of this area is that there are also a lot of cafes to have breakfast in, cheap pizza, and the like nearby. It can be a bit sketchy at night sometimes, but if you're with your friends I wouldn't worry too much.
Secondly, clubs and hangouts:
- Saphir: is a two-floor bar on rue Saint-Laurent at L'avenue des Pins. Take the 55 (or walk) from metro Saint-Laurent. The 'darkwave' night is Fridays on the 2nd floor. There are also retro 80s and rock/metal nights.
- Passeport: Saint-Denis between rues Rachel and Duluth. Walk from either Sherbrooke or Mont Royal metros. When I was last in town, the goth-industrial night was Thursday, but I'm not sure now beyond the fact that they do play various genres of alternative music on different nights.
- Cafe Chaos: a pub on rue Saint-Denis between rues Sherbrooke and Ontario. Quite a punk / general darkling hangout when I was last in town.
- Foufoune Electrique: rue Saint-Catherine just around the corner from metro Saint-Laurent. Three floors and an outdoor terrace in the summer. I don't know if they still have different DJs on each floor. In any case, it used to have some goth industrial stuff, I think it is mostly punk, metal and retro these days. Good to go to just to say you've been, I guess, it being subculturally (in?)famous and all, but last time I went the other clubs I mentioned above were way better than this one.
- There are probably others these days, but I don't know the details; I do however know where you can go ask, and I'll get to that below.
Thirdly, shopping: you may think this sounds crazy and/or like someone thinks about this way too much, but you can actually do the majority of the subcultural shopping in Montreal in one day if you are 'efficient.' Here is the route:
- Take the metro to Sherbrooke. Walk to Rue Saint-Denis. There are two punky/gothy stores here on opposite sides of the street, Rio and X20, and they both have boots, accessories, clothes, etc.
- Walk north up Saint-Denis to Ave du Mont-Royal. If you do this during the day you will then know where Passeport is when you come back at night. I think there may be some place selling mediaeval clothing along here, and possibly a comic book store, but I'm not sure since it's been a few years.
- Walk west on Ave du Mont-Royal, toward rue Saint-Laurent. Montreal's most well-known gothic clothing stores Cruella and Diabolik are both on this street, along with Rock Montreal (which is sort of like Charisma or Tropicana in Calgary), at least three different vintage/consignment stores, other accessory stores and etc. all packed into a distance of about 8 blocks. Also worth noting: Diabolik and Cruella tend to have fliers re: events going on in the city likely to interest dark subcultural folks.
- Go south on Saint-Laurent. You may want to take the bus, which comes pretty often, or you can walk: it's a ways but it's downhill at least. There used to be an army surplus store somewhere along here but I don't know if it's still there now. Also, you will pass by Saphir. Get off the bus at Saint-Laurent metro, which is at rue Saint-Catherine.
- Walk west on rue Saint-Catherine. On the corner at the intersection of Saint-Laurent is Romance, which is a very big lingerie store with some pretty interesting stuff in it. (If you go east instead of west on Saint-Catherine, you will pass Foufounes.)
- Keep walking west and eventually you will pass all of the following: a store with some really crazy boots in the window, a large HMV, Le Chateau and other similar stores which mysteriously contain way better clothes than you ever see in Calgary, a store that sells posters and metalhead stuff, Melange Magique (which is a lot like the Witchery in Calgary) and Sex Cite, another good adult/lingerie/fetish store.
- By the time you walk by all of this, you will be near metro Guy and will probably want to be taking it back to your hotel, since the stretch I discussed in #6 is about 20-30 blocks, and this entire route is about 50-60 blocks total. (It is hard to estimate distance-by-blocks in Montreal because often if you are going one direction - say, N/S - the blocks are 3x as long as if you are going the other direction - say, E/W.)
There are also 2 shopping destinations that are not on the route I mentioned. They are:
- The Le Chateau Outlet. Metro Namur on the orange line, rue Jean-Talon O. Tends to have all the awesome Le Chateau clothes going back years, as well as stuff that will probably make you go "this is awesome, why the hell was it never in the mall stores???"
- Il Bolero. Metro Jean-Talon (where the orange and blue lines cross), walk to rue Saint-Hubert. Go south on Saint-Hubert and you will find a number of interesting accessory, clothing and lingerie stores, as well as one comic book store that I remember has a lot of action figures. (I remember this because some friend borrowed quite a lot of money from me and spent the majority of it at that store the last time I was there.) In any case, Il Bolero is perhaps the most well-known fetish store in Montreal, and if you want info about those sorts of events, they may have fliers or be able to give advice if asked.
A few other points about the city:
- There are night buses, i.e. 24 hour transit although you may have to wait a little while. See the transit site.
- Montreal is more English as you go west of Saint-Laurent, and more French as you go east of it. Just something to keep in mind if you are particularly timid about trying to speak foreign languages, i.e. the further east of Berri you go the harder a time you are probably going to have.
- Speaking of language, if you don't want to speak French I recommend that you still try but make abundantly clear that you suck ass at it, at which point your average Montrealer will switch to English so they don't have to hear your terrible French anymore. While they are less opinionated about this than other parts of Quebec, I think this still tends to put them in a better humor than if you don't try and only speak English.
- In Montreal in summer, night tends to be pretty close in temperature to day. As a result, the number of people on Saint-Catherine at 1 AM is not as different from the number on Saint-Catherine at 1 PM as a Calgarian might expect. So if it's a nice hot day, you probably don't need to bring your coat to the concert/club/whatever on the assumption that it will get 'chilly' later the way you might in Calgary.
Hope this is helpful.
> at which point your average Montrealer will switch to English so they don't have to hear your terrible French anymore.
Ahaha this is exactly what happened repeatedly when I pulled out my high school french in an effort to be all diplomatique. Usually accompanied by an exasperated sigh and/or eyeroll.
There's a few things on your list that I'm pretty sure we missed when we were there last time. This is awesome, thank you!
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