In my humble opinion, the best and most unique tips out there are Brett's TruStone tips (he hand turns them, so no two are ever alike). They are gorgeous and after getting one, I never want to use anything else. They are a little difficult to get though, he posts them in his thread here on ECF first (usually in the evening, you can find the time for tonight in his thread) to give everyone a preview:
New wood, acrylic, and TruStone drip tips
Then he posts them on his website where you can buy them. You've got to be quick since there's only one of each, but they are SO worth it. Here's his site:
Bull Box Mods
He has a small gallery of his tips and wood box mods on his site if you want to take a look.