Atrios linked to this very handy site yesterday and I keep going back to it to play.
The "Neighbor Search" function lets you type in a name and find out how much, if any, they've contributed to presidential candidates.
Searching for the name "Bush," for example, reveals that the George W. Bush campaign has received the $2,000 maximum gift from George H.W. Bush, Barbara Bush and Marvin P. Bush — but nada from Neil. First the president blows off his brother's wedding, then Neil stiffs W's campaign. Brotherly love.
Meaningless, but fun: People with the surname "Bush" have donated more than $15,000 to democratic candidates. No one with the surname "Kerry" has donated anything to the president's campaign.
The site also has a search by zip code, which lets you check up on all the shakers and money-makers in your neighborhood.