My feet are mainly affected by this and only sometimes my legs.
After trying all kinds of things (sleep aids and meds only aggravated the problem). I have found something that is working great for me.
Since its really only my feet, I bought some magnetic shoe inserts and put these on with socks at night and sleep with them. No more twitches.

I tried this one time with my legs using an ace bandage to secure a couple of these magnetic sole inserts to my thigh.

You can find these fairly cheap on ebay.

Anyone let me know if this works for you.

Good Luck everyone.