I used to take wasps nests for fishing using the grub as bait, I used to get some saltpeter (dunno how to spell it) mix it with water and paint it on a newspaper, make a squib, light the squib and shove it down the hole where the nest is, wait about 5 mins and then dig like fuck with a spade, grab the cakes (what the grubs are in) put them in a bin bag and run like shite before the wasps come round or they'll have ya. Funny as fuck when theres a few of you doing it. They chase you for ages. But boy do they hurt when they get ya.
Nowadays, I just blow on them, it seems to put them off balance and they do one, or my breath stinks like shit.