I just re-stuffed my Lowepro Slingshot 200 AW for a job on Sunday. I was able to put the K20d wearing a Sigma 17-70, a K1000, a K100D, an AF280T flash, a Sigma 70-300 Macro, a Pentax DA 18-55, and a Pentax M50 f/1.4 all inside the main compartment. Lens hoods are on all the lenses except the M50.
I've got spare batteries, three CP filters, a ND filter, charger, USB cable, video cable, viewfinder cover all inside the upper compartment. In the front zipper pouch, I've got more batteries, the Pentax software disks for the K20, warranty information (such as deadlines for maintenance,) a LumiQuest pocket bouncer, model releases, and a lens cleaning kit.
Holy crap! I had no idea I could cram that much in there!!
The best part? Most of it was purchased with a gift card so it ended up only costing me $7!