Always enjoyed Wendy May's Locomotion at the T&C. Probably not everyones cup of tea, but fondly remember a summer night probably late 80's - a 9 Below Zero gig, kicked out for 1/2 hour then Norman Cook (post Housemartins) playing a Soul Set warming up for Wendy May.
Upstairs at the Alexandra in Clapham's been mentioned, & what about The Castle in Tooting?