In general, gaming peripherals for Macs are hard to come by; Razer has at least 3 keyboards that allegedly support Mac OS X; you might have to modify or get over keys (mis)labeled for windows users. In general, most gaming keyboards like to have a very tactile feel that allows one to be certain of keypresses. I'm not sure exactly what feature you are describing with 'clicky-keys'; are you looking for a long stroke, or for keys that register a keypress before bottoming out, and have significantly less resistance for the bottom portion of the stroke?
I'm describing the feel that you get with "mechanical-switch" keys (google it for images/explanations). The Apple Extended Keyboard (and Apple Extended Keyboard II), and, more recently, the Matias Tactile Pro (not ProTouch, whoops) are two keyboards that use such technology. Most other keyboards do not.
The Razer "for Mac" keyboards seem to have obviously non-Mac layouts, which rearrangement won't fix. That's a deal-breaker for me. The correct layout and the feel of a good keyboard is more important to me than additional keys or whatnot. My question was mostly due to curiosity.
Thus spake Eliezer:
It seems that many here might have outlandish ideas for ways of improving our lives. For instance, a recent post advocated installing really bright lights as a way to boost alertness and productivity. We should not adopt such hacks into our dogma until we're pretty sure they work; however, one way of knowing whether a crazy idea works is to try implementing it, and you may have more ideas than you're planning to implement.
So: please post all such lifehack ideas! Even if you haven't tried them, even if they seem unlikely to work. Post them separately, unless some other way would be more appropriate. If you've tried some idea and it hasn't worked, it would be useful to post that too.