Classically Casual, I've tried the Converse Cut-For-Chucks that
Greyscale linked to above, and they do work pretty well, except in my
higher cut, heavier sneakers. They're a little iffy in my New Balance
classics, and I prefer my Smartwool socks, similar to the ones Diana linked to, in those, even though they show a little more.
I wear these sometimes under oxfords and such: http://www.herroom.com/Hue-129.....v& . I got them at Nordstrom, but I don't see these exact ones online. They have a silicon patch at the heel that keeps them from slipping down. I've worn them under my Converse look-alikes, but I don't really like how they feel under sneakers. They definitely don't work under heavier sneakers.
Ugh, April, I know exactly what you mean. The pain that's caused when my
socks compress my toes too tightly is almost indescribable, and it's ultimately because of my bunion.