I was just scrolling around and I came across these trick aluminum Upper Control Arm's for our trucks. They are expensive as hell but they look pretty cool and I am sure they are very light weight. You can seem more here @ http://www.wheelersoffroad.com/05updonahoetacoma.htm (scroll down to the bottom to see UCA's)
I personally would buy them at the price of $995 w/ free shipping but maybe one of you would to be one of the first to have these.