My favorite is the Mauser HSc. I found a war issued HSc in the broken gun box at work and got a really good price for it. Turns out it only needed a new trigger spring. It started me on my love for the round.
Now I have several guns in .32acp, like a CZ 61, Beretta Tomcat, Keltec 32, Colt 1903 (which feels like shooting a .22lr), and a few others. But the Mauser got me started and you have to love those smooth, contured lines and futuristic look.