Black Truffle is a great shop in Broadway Market, definitely a hot spot to get to know when you're in London. Great ranges, and if you need a gift for a vegan friend, then they have a small but beautiful range of vegan friendly bags. I like this one in particular from Jack Gomme. It's squash, squidgy, kind of cuddly, and with plenty of room for all the rubbish/essentials we girls carry around!

And if you can't get to Broadway Market, then the Black Truffle website is pretty comprehensive.