Something that really upped my motivation for running is using my cellphone's gps to log data. I coded a small web-app to show a little bit of stats (http://fitness.marc-seeger.de/category/joggen / http://github.com/rb2k/run-a-log) as my first little project with ruby/sinatra. My inner nerd loves to collect data and do stuff with it and my body is probably thankful for it (just finished my 800th recorded kilometer)

p.s. I currently use "cardio trainer" on android which would also offer a webinterface to data. Before that I used MyTracks (android), Nokia Sportstracker (Symbian), jogstats (webos)