And I thought custom jeans were cool (no, I still haven't ordered a pair), check out this site: http://www.createmychocolate.com/ where you can literally create your chocolate bar. You choose the type of chocolate, dark, milk, white or a combination of milk and white then you choose what to put in and on your chocolate. There is fruit, spices, nuts, candy, and grains (which includes fun stuff like cereal, pretzels and bacon -- yes, bacon!). You can choose up to 5 toppings, mix-ins, etc.
It is a little expensive for chocolate. I put together a creation for fun of strawberries, caramel and pretzels with milk chocolate and with the cost of delivery it comes to about $15. Probably a little much to indulge for yourself, however, they sell gift certificates and I think that would be a pretty cool gift to give.
Another site doing something similar is You Bar: http://www.youbars.com/custombars where you can create custom protein/energy bars. The best part of this site is that it gives nutritional information as you go along so if you're trying to stay within certain limits on carbs or sugar or fat, it is really easy. Plus you get to name your bar and they create a customized wrapper with your name on it for each bar. That's fun! Lately I've been into making my own granola bars, but when I get tired of that, I may just have to give this a try.
You Bar also has sites for Trail Mix, Shakes, Cereal, and Cookies.
Can you tell I'm hungry right now?