While, when I'm taken out to eat, I'd love to know how much tip is left, it's one thing I have no control over. But, I went out w/ some friends yesterday and all but one person left cash. She took the cash and put the whole bill on her credit card which is fine. All of us at the table have done that at some point. The rest of us eat out occasionally and we're all big tippers. She never counted how much money she collected, just assumed we'd all put in the right amount. She's not the type to intentionally cheat anyone but after she signed her tab, I wondered if she tipped enough, including what we all ("over") tipped. I'm wondering, for the future, if there's any way to ask how much she left?