I have used lots of keyboards over the years and some of them have had very quiet and mushy feeling keys while some of them have been very tactile and clicky. The only downside to the clicky keyboards is that they make lots of noise and while it didn't bother me, my wife would come into my office and tell me to stop hitting the keys so hard.
One of the louder and clickier keyboards out there is the Das Keyboard. The Das Keyboard first made its name with the original model that lacks any print on the key tops. You really had to be a good touch typist to use the thing. Thankfully, the company came out with a version with letters for those of us who like to hunt and peck.
The company behind the Das Keyboard has come up with a cheeky solution to fix the problem of noisy keys for your co-workers -- earplugs. The earplugs will ship with both versions of the Das keyboard and can be purchased separately online for $9.95 per set. If you want to save that $10, you might just suggest that co-workers plug their ears with those cheap, rough, brown paper towels so popular in offices today.