Daft Punk - "One More Time" (2000)
An absolute classic of the genre, and responsible for thousands and thousands of imitators.
I think it goes without saying that I think this song is terrible. It is almost everything I found bad about music in one long repetitive track. That being said, I will attempt to find some nice things to say about it. The middle section, starting around 2:22 is not as annoying as the rest of the track, because the drum machine has been turned off. They use a great bass sample even if they claim that it wasn't sample. If they played it themselves, great. The song ends so surprisingly abruptly I thought YouTube had choked. The lyrics are very upbeat.