In hopes of finding a longer-lasting keyboard, I've been using a Key Tronic keyboard I picked up at an office liquidation store. Since I acquired it in late 2003, five letters have at least halfway rubbed off the key caps. The wear will probably accelerate if past keyboards are any indication, but it's satisfyingly clicky compared to the overpriced "soft touch" keyboard it replaced. (I hated it, but it was the only keyboard I could find in Goldsboro had that didn't have a "natural" layout or all those extra buttons for features like volume control.)
In a perfect world, I'd be typing this on an IBM Model M (unofficial motto: "Type hard or go home") or a Northgate (more likely a CVT Avant keyboard, which are reportedly based on Northgate keyboards). Alas, I own neither and they're rather pricey. Whatever I eventually replace this keyboard with will not have Windows keys because they bug the crap out of me, which in turn bugs Vogon since I remapped them on my system. Heh heh.
edit 2100: I picked up a Model M made between 1989-1993 on eBay with Buy It Now (I prefer it to bidding on most items since I don't use a sniping service or whatever) for $26 including shipping. I am pleased.