Yes, I had a couple of pen pals who rode out my bid with me. One I met in the visiting room (she was visiting another inmate), where we had a physical attraction. That pen pal seemed more real to me, I made greater efforts to let myself be more open than the one who just started writing me (from a news account of my trial). Neither went beyond the intimate letters and occasional phone calls. They bought me magazines and books, which I will be forever grateful, but I tried not to take advantage of their generosity because somewhere inside me i knew that i wasn't going to hit them up when i got out.
I didn't make an effort to continue and have never heard from either again. If you are asking my advice, I'd say not to believe too much "love stuff". We inmates are lonely, and most guys I knew would say ANYTHING to keep their penpals writing and sending money, etc. Be careful not to let your guard down or do anything for them that you know you shouldn't - inmates say things, make promises and then never keep in contact - the people on the outside get hurt emotionally when reality sets in.