The other night I'd say maybe 10-15mg altogether, accounting for redoses and such. I've had it before and tried tiny amounts to great success but it's never had the pronounced effect it did the other night before.
Edit: To make it clearer I'd been experimenting with tiny doses and getting a nice, focused feeling but I'm a bit scared of new drugs so it's only when my inhibitions are gone that I'll go all out. I'm glad I did as the experience was pretty great and the euphoria was a lot more than I expected, though I tend to be very cocky when I'm slightly drunk too.
The other night I hadn't touched the stuff for at least a month, though.