Not too bulky, likely to might save it in a minor fall.
Any recommendations?
Otterbox
There's 3 different ones, with varying protection. I've got the middle one (£19 off eBay) which is a rubber case with a plastic outer to keep it in place and a full screen protector. I've dropped mine a couple of times with no damage. I did cover the back of the phone with clear tape too, because I found grit got inside the case and scratched the phone with my 3G
Otterbox here too - I am clumsy.
I refused to pay the £15-£20 the shops were asking and bought a selection off ebay. None of them were more than £3 and they all seem fine. I have a full (faux) leather one for when it's in my backpack and a rubber one which leaves the screen on display (with a plastic cover over it which came with one of the cases) but covers the back and the corners which is what i use mostly (£1.99) and a few others which i tried as well. All in i bought 5 to try and still only spent around a tenner.