I've been trying to find a saddlebag that won't cost me a lot of dough, and after looking around a lot that seemed somewhat impossible if I wanted anything of decent quality.
So until I can afford my ideal saddlebags, I grabbed an old army surplus backpack I had lying around, and looped the straps under my seat. I kept my cargo net on there for when I pack pretty full since it's not totally closed on top.
Perhaps not the most elegant or aesthetically pleasing solution, but it holds my crap, and that's what I need right now. I think I paid around $15 for the bag from a local surplus store a couple of years ago.
Just thought I'd share in case anybody else is looking for a cheap way to hold their stuff until they can afford something better.
P.S. No that's not a giant oil spill under my bonnie, just water to clean up a little spillage during my last oil change.