I initially used a cheap rear rack from Performance, but recently replaced it with the sturdier Old Man Mountain Red Rock rack. It's considerably more solid and has a 60 pound weight capacity. Its longer and attaches to the brake bosses, allowing it to sit farther back pretty much eliminating any problems with heel strike.

I use an Arkel Commuter pannier (plus rain cover) for commuting. It has a removable, padded laptop compartment and a really nice attachment system. I use a pair of Nashbar Townie baskets for grocery shopping and miscellaneous errands. It's nice that you can fold them flat and that they come with their own rain covers.

I used SKS P35 fenders for quite a while, but kept having problems with toe overlap (hitting the fender with my feet while turning and pedaling). I replaced them with some Planet Bike clip-ons which have worked out well for me. They also look a little better on the Tricross, IMHO, than full fenders.

Jimlamb, I've been procrastinating about getting a rack for my Tricross because up until now I've not seen anything that grabs me. This Arkel looks very interesting though. Also like many of your other accessories. Would you have a picture of your rig fully equipped to post?