Nike+ running system, I realized it was going to be an excellent motivational tool. The system encourages you to set goals, or join challenges with people from all around the world.
In addition to the above, it rewards your runs by assigning you a "level" depending on how many kilometers you have run. Levels (and the associated colors) are assigned as follows:
Yellow (0-49km, 0-30mi)
Orange (50-249km, 31-154mi)
Green (250-999km, 155-620mi)
Blue (1,000-2,499km, 621-1552mi)
Purple (2,500-4,999km, 1553-3106mi)
Black (over 5000km or 3107mi)
I just hit level "BLUE", which means I have run over 1000K since I started using the Nike+ system. Here's my run summary.
I started using the system in late January (a little less than 5 months ago), so it also means I have been running an average of 200 kilometers per month.
At this rate, I should hit the "PURPLE" level somewhere in February 2011.