Shimano PD-M959 for Summer:
http://tinyurl.com/khwwq
These are fairly light for an SPD pedal. The spring tension is pretty high compared to the other Shimano SPD pedals I have used.
Shimano PD-M647 for Winter:
http://tinyurl.com/f8k9b
These a really nice. The spring tension is nice and light on the lowest setting making them easy to get in and out of. They are a bit heavy, but not compared to most standard platform pedals. Being able to use them with any footwear is a big plus.
I have a set of the PD-MX30 platforms too. I don't use them much anymore. It's nice to have a set of regular old platforms around, anyway.
Speedplays Frogs are nice enough. They clog up easier than the SPD's though.
Has anyone used those Ritchey Micro pedals? They look kind of interesting. Do they use a std Shimano SPD cleat?