I recently joined a gym which is great and all except for the fact they only got like 2 ab machines and one seems to be broken and the other is mostly used during personal training circuits provided around the time I always get there so I gotta wait till the end of my workout to be able to use >_< I was thinking there must be other ways to exercise my abs and try to tone them up. I know there must be an ab machine out there that works.

I am willing to spend anywhere up to about 100 dollars but I want to get the best I can get for my money. Also I can't do situps due to the fact that they always hurt my lower spine/tailbone and the back of my neck so its rather futile to even try. Crunches cause less pain but I still feel I am not quite getting the exercise I should get out of them. Has anyone used any to recommend? Any I should avoid like a plauge? gonk I've read so many mixed reviews on amazon.com and other sites that I am really confused as if there's ANY that actually work (if they were all terrible all exercise companies would be out of business by now rofl )