I take 2 usually before going out (on days only when I've only taken a maximum of 25mg already) as I find it helps me stay awake and alert. It also seems to increase my tolerance; once I get past a certain "drunkeness" I can just keep drinking for a long long time, much more than normal. Unfortunately, of course, I end up drinking till I go to bed. Hangovers the next day are redonkulous, I'm not sure if because of the ephedrine use + alcohol or just the fact that one can drink so much more and not realize it.
Oh and for the record I know all about ephedrine use, I just heard that it could be used in combination with drinking for a positive effect and tried it one day. I don't abuse ephedrine and I don't use it all the time before going out, just when I'm really tired.