Hi C.,
I too was put on bed rest (& I had to stay in the hospital) for a month before my 1st child was born. I shopped on the internet for baby things, read, watched tv, and taught myself how to knit. I made a blanket for the baby (it ended up being REALLY big since I was on bedrest for so long :) )but staying busy and making progess on something made me feel productive. Maybe catch up with old friends via internet,phone or letter. Watch some movies that you've been meaning to or start working on a baby book.
It is hard to keep your spirits up but when I was on bedrest I figured I'd just take that time for myself and relax since once the baby comes those days will be long gone! Plus, I figured everyday that past was one more day my baby was able to grow bigger & healther in utero.
Hope this helps & good luck to you.