how do you deal with heavy power cords?

I have the same problem.
This might work for the wall outlet, though I haven't tried it:

http://www.buypowergear.com/detail.aspx?ID=5165

As for the IEC end, everything I've seen requires holes to screw into, like these:

http://www.qualtekusa.com/catalog/na_power/retainer.html

If you find something better, let us know.

i have jps 'aluminatas and they,too,are very heavy...what i did was to make a 1" thick wood block with cut outs for the outlets...i have a quad outlet...and take velcro tape and tape the wood block to the outer limits of the wall outlet with the velcro....then plug the pcs' through the holes into the outlets..the 1" wood thickness holds the plugs in nicely and does not allow them to lever out...hope this helps

Only thing that I have found that works for me is to cut out a piece of wood (but any other materials would probably work too, even found around the house) and prop up the cable. I use blueTack then to prevent this piece from moving. Since I am not moving around equipment, as I am able to pull my complete rack out, this is the only thing that has worked for me.

For the wall outlet, I have not experienced this problem. But you can also bend out the prongs a little bit to get a tighter fit to help it hold in better.

Put a cable tie (that has an added eyelet) around the power cord and then affix a hook to a nearby surface and hang the cable from it. You can also double them up and attach them to a chassis screw or around the feet of your amp and other component

http://www.cabletiesplus.com/Products/5-Mounted-Head-Cable-Ties-(40-lb)-(Natural)__CP-5-40MH-N.aspx

thanks! I bookmarked the links and will try all these suggestions until I find one that works for me. The buypowergear clamps look interesting.