I was wondering if anyone has made any of their own equipment or knows of any good resources for making homemade equipment.

I have a pretty nice home gym, but want to add some things. I have trained at the gym and at home, but lately I have had more of an interest of training at my home gym. This is what I have at the moment that is not homemade...

A power rack w/ pullup bar and dip attatchment
Cable lat pull and row
Leg Ext
Seated Leg curl
Nautilus Seated Calf
Nautilus Leg Press/ hack squat
Dumbells from 5-110 lbs
preacher curl bench
adjustable bench

I would like to add a Grappler (westside barbell invention), a cable hip squat machine, and I have plans for a cable lifting system that works like a smith machine. I also want to add some medicine balls and other lifting implements.

I have made a cable crossover machine, and two thick handled barbells (2 inch and 3 inch). I am only making the equipment for myself that I feel will hold up and be safe. I am only using the strongest materials. Does anyone have any other ideas or suggestions?