I push Ektachrome 320T one, two or three stops (metering EI 640, 1000 or 1600 respectively), Portra 800 two stops (EI 1600 to 2000) and Fuji NPZ two stops (EI 1250 to 1600).
Results from those pushes:
Colours are natural with the EPJ, natural-vivid with Portra 800 and vivid with NPZ. The EPJ is grainy, the two negs films have amazingly low graininess with the Portra beating the NPZ in terms of higher usable speed, better colour fidelity and slightly lower graininess.
I don't think that it's worth pushing neg film one stop, but it is worth tuning reversal film stop-by-stop when pushing. My chosen meter settings are based on preferred mid-tone placement.
Nowadays, pushed EPJ and Portra 800 are my most used still films, bar none. I also push Ektachrome E200 now and then - which lets me use it as an all-purpose slide film when travelling. Two stop pushed is metered at EI 640 and three at EI 1000.
I've been testing 400UC, and it pushes well, but I prefer Portra 800. A dozen rolls of Fuji Natura (1600) have just arrived from Japan, so I'll try those pushed two as well as normal.