Websites that've playfully reminded me to vote:
Facebook, right in the header.

Google AdWords -- in the Campaign Management dashboard.

MySpace, between pages. This is actually an interstitial ad for E-Research Council, but still.

Meanwhile, traditional media entities like PBS have partnered with Google to make this year's election the
most transparent ever. Got a mobile cam? Covertly
video your experience at the ballots.
Twitter and
My Fair Election are also using crowdsourcing to police the polls this year.
Other sites jumped the gun: betting destinations
cast lots for Obama, and even Facebook Lexicon "suggests" (eh, I'm iffy about this)
an Obama win.
We'll know in 12 hours.