For men, my classic pick is Brooks Brothers' sterling silver button cuff-links mainly because I like the idea of a sterling silver button in place of a regular button. They are $125; available here.
For something less classic, I would go to Thomas Pink, which has a collection of really interesting, yet not overbearing sterling silver cuff-links in the shape of animals -- including many animals I would never have thought to put on cuff-links, such as rats (£85), pink panthers (£75), bulldogs (£75), and a really large fox that is the Pink icon (£85). However, my favorite by far is the silver robot cuff-links complete with a lapis lazuli stone as a body and eyes made of red crystals. They are £99; available here.