I'm definitely mostly into modern history myself, which seems very neglected in terms of RP. Pretty much the only 20th century events I typically see RP's centered around are 1920's America and WW II. A lot of people seem to overlook the absolute gold mine of plots that can be played in the 20th century. There was plenty of tension, political intrigue, cultural upheaval, etc. It's very under-rated as far as RP goes. I personally just finished a 1x1 RP set in revolutionary Russia and it was easily one of my most memorable.