Like the others in the Northeast, pleasant weather, mid 70s, nice and dry with a bit of a breeze on the ride in this AM. Unfortunately the ride wasn't without it's difficulties... about 3 pedal strokes from home my chain failed when a link shattered. That chain was probably OEM from the mid 90s and was in rough shape with tight links and some rust. Turned around, walked home, put the bike up on the repair stand and threaded an old chain onto the drivetrain. Got back on the road after about 10 minutes. A couple minutes later, I was accelerating through a fairly busy intersection and a heel strike knocked my pannier (BTW, I hate the Trek grocery panniers, had this issue before) off the read rack. Some of the contents spilled onto the roadway so I pulled over and retrieved the pannier and contents which had been kindly avoided by motorists. I repacked the contents and reattached the pannier, made the intersection crossing as a pedestrian and got back underway. A short time later I was accelerating again and nudged the pannier causing one of the hooks to come off the rack and the backing to rub against the rear wheel. I pulled over and reattached the pannier once again and was off. At this point I felt kinda cursed (full moon?) so I rode slowly and deliberately the rest of the way to work. The panniers will be empty on the way home, so hopefully I'll avoid any more issues.