* REI shopping panniers (my favourite)
* small single pannier from MEC
* large single waterproof pannier from MEC (oh, I hate this thing -- cumbersome and the clips for the rack never really clasp shut or if they do, they jam)
* bottomless pit of a LL Bean nylon rucksack (only worn on my bike if I'm carrying light, bulky stuff)
* small Gregory silicone backpack for daylong rides (holds a 2 litre water bladder and hose). I love this one! The waist strap has long mesh pockets that are perfect for holding my wallet, change wallet, cellphone and keys.

I also have a handlebar basket that holds a myriad of stuff on my commutes and fun rides. If I don't need to lug around a pannier (or two), I prefer bringing my stuff in a fabric shopping bag that can sit easily in the basket. Much easier to carry around and still can bring home a few groceries or library books.