I have a
Logitech G600 as a product of my MMO gaming and it's integrated into the rest of my games almost seamlessly. In DotA 2, I use the buttons for my items. In Minecraft, a button corresponds with a slot on my main bar, so by keeping my bar organized, I've managed to fit into a system where each button almost always correlates with a certain feature (1 Pickaxe, 2 Shovel, 3 Sword, 4 Axe / Other tool, 5 Bucket, 6 Torches, etc.) and I can easily switch between them with just my thumb without having to always look at the bar.
If you're big on video games and/or play a lot of games that have bindings on the number keys (or that you could bind to the number keys) such as hotkey MMOs, (A)RTS games, and potentially Minecraft (if you use the number keys for your bar), I recommend one of these. It's similar to the
Razer Naga but I've heard Razers typically have problems after about a year of wear and tear.
One of these is going to run you a big fat price tag though, so if you aren't going to be extensively using the features, just pick yourself up a cheap Logitech - Logitech hardware is durable, long-lasting, and comfortable to use.