Since i started in photography I always had a 50. Then, with my FM2 I bought a 105mm that I used as a tele lens for press events. Then added a 20mm.
When I moved to Canon digital I bought 24-70L , 70-200L and a 20mm, for comercial use. But soon I started to buy a 50/1.4, a 85/1.8 and the last one (that I wanted for many years) a 35/1.4L.
Now I am on M9 with a borrowed 35 cron and looking for a 50, cron or lux. That's my prefered lens. And after the 50 I will buy a 35.
When I travel, I did many trips with my FM2 + 50mm + 20mm. Now I like to travel light and the M9 + iPhone Hipstamatic are my best options.
By the way, if anyone knows of a nice 50 cron or lux, please let me know! Thanks!