Be warned - the Zatchels one is like an anti-Tardis, even the large size. I bought one for £25 in the sale last year and I've used it all of once. The flap makes it look so much bigger than it is - the actual bag part is tiny, barely big enough for a small purse, diary, glasses case and phone. The leather is really stiff too so there's no 'give'. They are absolutely beautiful but pretty much pointless if you need to carry more than the bare essentials.
M&S had 30% off all their leather bags last week - not sure if they still do. They have some lovely bucket-style cross-body ones.
The Lilith doctor bag from Gusti leather is my current favourite - it looks small but because it's got a wide bottom (I know the feeling) and is really soft, you can fit loads in. The frame opening is excellent too because you can see all your junk belongings easily. I can get all my crap stuff in mine including a bottle of water and umbrella with room to spare.
