I use my 35cm Birkin for work, but find myself wanting a smaller bag or clutch to use when "running out to lunch". I don't want to lug my Birkin with me if all I need is my wallet, blackberry and phone. Also, I'd like to be able to throw the small bag into my Birkin. (I'm too scratch-averse to get a box clutch to throw in my bag!!) And I don't want the bag to look like a toiletry case... What do you use? Thanks!