Not sure why this site has a different RPI than the other site, the formula is straightforward math, but regardless it is pretty close.
This site also shows a projection of where teams will end up, groups by conference, etc. I think it is pretty fun to mess around with.
One of the interesting things to me is that on each team's page it shows a list of all of the teams that impact the team's RPI (both currently and in the future). Amazing how many teams' performances impact each team's RPI since it factors in opponents' opponents' records. Go High Point! (except when they play Arkansas since Arkansas impacts us a lot more)
http://www.rpiforecast.com/confs/Amer.html