100 reps a day challenge

Anyone watching my Twitter feed (@mykevandyke, or just take a look over to the right on the main page of this site), can see I am doing the firefighter "100 reps a day" challenge (hashtag #100RepsADay). The idea is to do 100 of something (there is a list for January, I assume the one for February will be coming soon) every day -- the exercise changes every day.
The challenge comes from firefighter functional fitness (@FirefighterFFit).