Way before I discovered the bar-barian community I was doing 300 work outs. 300 work outs came to popularity when the movie 300 came out which was filled with ripped dudes everywhere. The workouts that much of the cast went through to get in this sort of shape became an exercise fad. Read my background on it here - http://duf.net/300qa.htm
The work out I was doing was actually sort of the final exam for people that went through the training. The object was to complete all 300 reps in as short of a period as possible. I read of someone on the cast doing it in around 18 minutes which is pretty awesome.
Anyway, I did this work out religiously for a good two years, either once or twice a week. Even though I used what I now know if very poor form (nowhere close to full ROM) on exercises like the pull ups and push ups, it still kicked my a$$ big time and helped me chop a good 10-15pounds of chub off my body.
I got away from the workout for a while due to various injuries and a change to a gym that wasn't very 300 friendly.
Well a few months back I started doing a new modification to the 300 (invented by me, myself and I), 300 Version 2.0. In the original 300 you were doing 50 reps of 6 exercises. All of these sets were done at once (you complete all 50 reps of one exercise before moving to next) besides the pull ups that were broken apart into 25 at the start and the end.
In 2.0 I have changed it to be more of a circuit where I am only doing 5 different exercises but I am doing them in three sets of 20. I also mix up the exercises from week to week instead of doing the exact same stuff week in and week out like the original 300. So I do 20 of one exercise, 20 of the next, 20 of the next, etc.. and then repeat the circuit 3 times.
Today I tweaked it a little more and I really liked the results. By the end of it I was totally spent, just like I should be. It went like this.
The exercises were pull ups, dead lifts with 135 pounds, body weight dips, 30 inch box jumps (full extension at top) and 40 pound one handed clean & press (alternating hands)
I would not be able to do three sets of 20 pull ups at a time. Instead I did sets of 5 pull ups in between every other exercise set. I would rotate my grip for each set of 5 between pull, chin and neutral. It really worked out great. So it looked like this:
20 - dead lifts
5 - pull ups
20 - dips
5 - neutral grip pull ups
20 - 30 inch box jumps
5 - chin ups
20 - 40lb clean & press (10 reps with each hand)
That was one circuit. Repeat three times and you should wind up with 300 total reps.
Of course as with any circuit training, the key is to try to minimize your rest between sets as much as possible. Try working one of these workouts in every week or two and see how it pushes your limits.
Like I said, I mix up the exercises I use each time, some of the exercises you could use are:
Diamond Push ups
Stiff legged leg lifts
Clean & press
If you would like to see my ongoing 300 workout log it is online here - http://duf.net/300.htm