Robert Scoble's embarrassment over forgetting to pay a restaurant bill reminds me of an even more embarrassing incident experienced by a component team from the Windows 95 team.
To celebrate something or other, their team went to lunch at The Salish Lodge, a fine dining establishment. At the end of the meal, everybody thought somebody else was going to handle the bill, and they all walked out as a group. The administrative assistant who made the reservation received a somewhat concerned telephone call from the restaurant when they discovered that a large party just skipped the check. Profuse apologies were extended and the bill was settled over the phone (with what I assume was a very generous tip). I just happened to be in the hallway when this whole thing happened and got to hear the story from the very exasperated administrative assistant shortly after it transpired.
So remember, folks: Pay the bill before leaving the restaurant. It saves everybody a lot of grief.