Have done a lot of things buzzed (including watching the Matrix,
sankalpa whither art thou?), but have never really given a scientific talk before.. It was just lab meeting - so nothing earth-shatteringly disastrous, but definitely something everyone in science must do once.
The potent chinese brew (think something between feni and toddy) was ostensibly consumed in honour of the coming of age of an under-grad. labmate. I think I acquited myself reasonably, of course it didn't hurt that everyone listening was also suitably buzzed..