Allow users to buy a number of items that others can take later
It would be great if Splitwise allowed for one user to enter that they bought a number of items (e.g. bottles of beer), that not immediately have to be split up between the group's users. Others would later just press a button that says "I took a one" and splitwise would figure out the rest.
And maybe warn you if you're out of beer. Cause that's bad.

We will probably add the ability to save a split by shares at some point, in which case you would just change the number of shares on the expense for each beer you took, but we do not plan to add a more specific feature to handle this kind of thing at this time.
Marshall