I really doubt Google would do this, not just because of potential contracts or even the lost revenue but mainly because of how tentative their market share is.
The only thing locking most people into Google search is habit. If Google were to not work for a day, a ton of people would start using Bing and friends; a significant proportion of these would indubitably continue using them forever. Most people don't really care about which engine they use--until it fails. Once it fails, they'll flail around for a bit then use somebody else.
I think the damage to Google's reputation and market share would be too big for them to consider killing search for a day. I could see them doing a doodle or something though.
The only thing locking most people into Google search is habit. If Google were to not work for a day, a ton of people would start using Bing and friends; a significant proportion of these would indubitably continue using them forever. Most people don't really care about which engine they use--until it fails. Once it fails, they'll flail around for a bit then use somebody else.
I think the damage to Google's reputation and market share would be too big for them to consider killing search for a day. I could see them doing a doodle or something though.