I also have to put a plug in for the Cool Running log (also free). You can track any kind of activity, not just running. It doesn't have as many neato features as bikejournal for cycling, but I'm finding it suits my cross training tendencies much better. The two things I really like about it are that you can download your journal into Excel and you can track ANY kind of activity. I have running, trail running, treadmill running, road cycling, mountain biking, skate skiing, telemark skiing, ski touring, hiking, weight training, etc...you get the picture.