Not sure what kind of music you play, but I used to perform live improvised electronic music either solo, or with one other musician. My set up was:
-wavetable synth with multitrack capability, I would set up independent effect chains on different tracks, so I could get a loop going and move on without disturbing it
-LG Sweep Function Generator, an audio diagnostic device that produces simple waveforms, and does complex modulations
-a cheap am/fm radio with a condenser mic, and some effects pedals
-an old akai sampler
I would run everything both direct to the board, and to the sampler as single tracks and a two mix. It let me grab stuff out of the air basically.
When it went well it was good fun.