Here is where I am today.
Primes
Pentax smc P-FA 20mm f2.8
Pentax smc P-M 28mm f3.5
Pentax smc P-FA 35mm f2.0
Pentax smc P-A 50mm f1.4
Pentax smc P-FA 50mm f1.4
Pentax smc P-FA 77mm f1.8
Pentax smc P-FA 135mm f2.8
Pentax smc P-M 200mm f4.0
Pentax smc P-A* 300mm f4.0
Pentax smc-F 1.7X AF Rear Converter
Zooms
Pentax smc P-DA 10-17mm Fish Eye f3.5–4.5
Tamron XR Di LD 28-75mm f2.8
Pentax smc P-FA 28-105mm f3.2–f4.5
Pentax smc P-A 35-105mm f3.5
Sigma EX APO 70-200mm f2.8
I've actually sold more lenses than I've bought lately. I may sell a couple more. My primary glass are the Tamron 28-75, and the Sigma 70-200.
The one hole I have is rectilinear WA. I'm thinking the DA12-24 may be my next purchase. I'm also thinking about the DA*60-250 to supplement the Sigma - only cause, as good as the Tamron and Sigma are, it bothers me that neither of my primary lenses are Pentax glass (purely an emotional response of course
).