I went back 7 pages and only found one article posted by WG.

I lift 4 days a week (on B days I do side bends for obliques)
I do Great Abs about 4-5 times a week (laugh if you will but it is working).

I'd like to find a good core workout that I could do on my 'off' days. The only caveat right now is that I have no where to do pullups or hanging leg raises or anything which requires a pullup bar. Any websites/books/vids would be greatly appreciated. I went to Border's Books but there are like 1000 books on fitness, 200 of which are core related (caveat: the previous statement may be an exaggeration)

Do Sanchin Kata

Ha ha ha

(no seriously do it!)

I found a good core conditioning workout that El Macho posted:
50 crunches
30 situps
10 back hyperextensions

3x a day.

These may give good ideas on core conditioning, too. Enjoy!

http://www.youtube.com/watch?v=kjk8aqMP1xQ

http://www.youtube.com/watch?v=kjk8aqMP1xQ

http://www.youtube.com/watch?v=lmpZAXhNFKA

http://www.youtube.com/watch?v=lmpZAXhNFKA

http://www.youtube.com/watch?v=KuRsKjq7j8k

http://www.youtube.com/watch?v=KuRsKjq7j8k

http://www.youtube.com/watch?v=mtHFEAQmKTU

http://www.youtube.com/watch?v=mtHFEAQmKTU

http://www.t-nation.com/findArticle.do?article=07-054-training

Thanks.

I started boxing a few months ago. Prior to that, I had almost never done any traditional "ab" exercises. Yet I was able to easily out-crunch most of the other students in the class when doing ab work at the end. How? Squats and pullups.

I don't rate crunches, a lot of people put too much emphasis on them, not necessarily anyone in this thread but just in general.

Compound movements are your friend.

Front squats and standing overhead presses (specially the later with 5RM load or less) grinds your core in a very, very good way.

One arm dumbell snatches are a killer too, barbell would be even harder!

You mentioned you wanted something for off-days? So you want something that'll maintain what you've built up in your real core work, but not so much that it starts interfering with the new mass and tone formation that's the result of that real work (remembering that muscle cannot build at the exact same time that it's being overloaded). Also, you want something that leaves you plenty of time for other muscles you're really working on "off days" for your core.

I'm an old guy, so I have an old-fashioned suggestion that might fit the bill: timed V-sits. Start one your back with only your glutes touching the floor, shoulders and feet about a handspan off the floor. Slowly raise both feet and shoulders until your forward-reaching hands can touch your feet, and then slowly back down to handspan-off-the-floor. The first time, time it so that it takes five seconds to go from near-straight to V-sit, and then five seconds back down to handspan. The next one even slower: ten seconds up, ten down. Then fifteen seconds up and down, then twenty. Twenty-five. Thirty. Then reduce the times in five-second increments until you're back at five seconds to get to V, five down.

If this isn't enough, start at thirty-second timings and work your way up to a full minute. Add slow twist-Vs for the obliques. Don't let your feet or shoulders touch the floor at all during this, not unless you're interested in possible long-term lower back problems.