I wear comfy pajama pants, or little shorts, and a cami top usually. Sometimes I'll sleep naked or just in underwear if it's really hot and I don't have to worry about someone walking in on me.
If it's warm out, I sleep in the nude.
If it's cold, pj pants and a tshirt, or sweatshirt.
Other times, a nice nightgown; sometimes a sexy one, other times just a comfy one.
I normally sleep nude or in undies. I'll occasionally break out an oversized t-shirt and PJ bottoms if I'm in the mood. I'm not really into "sexy" PJs, so I'll just have to hope that certain someone finds baggy Transformers shirts cute.