Well I just finished my trip through the year charts for Billboard from 1946-2010. I guess I started doing this sometime in July maybe? Any who it got put on the back burner a lot but I'm finally done.
Out of the ~5800 songs I went through, only 134 made in into the actual playlist I plan on keeping around. I didn't add any music that I already owned, so this isn't the best representation of my choices in music. A little more than 50% of the songs are from before the 80s, which makes sense as I've been listening to the Oldies station as long as I can remember.
For your amusement I'll provide a link to the YouTube playlist, around 20 of the songs are on a separate list entitled 'SME Jerks' because they don't actually allow playback in playlists. It's all more or less chronological, so if you dislike oldies and want to see what more recent songs are on there just scroll down.
http://www.youtube.com/user/TigersharkIV?feature=mhee#p/p