Peter Sagans power profile for his stage 1 win at this years Tour de France 2012
Sagan averaged 490 watts for the last 2.5 minutes of the stage and that was after 5 hrs on the bike
The last sprint to the line Sagan hit 1230 watts and averaged over 950 watts for the last couple of hundred meters.
Sagans stats for the stage:
Average: 210watts, cadence 72rpm with 2000 mtrs altitude gain and 3550 kilocals burnt.