Right now, Amazon (in the US) has 24-exposure 35mm Fomapan 100 on sale for $2.59 a roll. You have to buy $25 of merchandise from them to get this price — but that can be 10 rolls of this very film. Who knows how long this will last, so if this appeals to you go buy some now here.
Fomapan 100 is a beautiful classic cubic-grain black-and-white film. I find that it tends toward blown highlights, but other film photographers tell me that if I would just process it myself (rather than sending it to a lab) I could control that easily. Check out my review of this film here.