Cross over gear.........

[Tar Snake]

I bought some of those Arborware canvas pants when I was about 10lbs heavier than I am now. I wasn't wearing them since they were too loose. Recently I tried them as overpants for commuting and they work great.

I put on my normal dockers/dress shirt/belt worker bee uniform then the canvas pants go right over, no belt. They stay up fine and when I get to work they come off in under 10 secs. My work clothes don't get wrinkled, since my commute only takes about 15 mins or so.

I tried just riding in slacks and a leather jacket, but it feels weird knowing if you go down your pants are going th shred instantly!

Carhartt's, Dickie's et al would probably work too.

[Medic09]

+1 on the work boots.  My favorites for daily riding are my Ariat cowboy lace up work boots.  Look half way decent, have thick sole (advantage for short legged me) and can be polished up.  They are a bit heavy, but not too expensive.

For packing, I use the same compression stuff sacks that I use for backpacking and climbing.  There are now dry bag stuff sacks made of very light materials with a permeable material in the bottom that allows squeezing out the air.  I used some on a recent week long trip, and they took up significantly less space in the saddle bags. Aerostich sells them, but they're available at REI and any other hiking gear shop.

For insulation, I use all the same layers as for winter camping.  Silk, Smartwool, fleece.

[Yankee Dog]

Army field pant liners.  $11 and six buttons sewn into my over pants and my legs are good down into the 20s.  Super comfy and very lightweight.  

yankee Dog

[maddjack]

Padded bycycle shorts,great asset for long distance rides,also cool weather bycycle tights or pants,tried these this year and man they rock,I get this stuff local too at this outfits factory,great gear ,good prices for top of the line.
http://www.aerotechdesigns.com

Also work (Special Response Team boots) I favor Bates,HiTec,or one of the other ones from US Calvery store online.
Camping stuff,namely compression straps,waterproof bags and other gear made to go into backpacks,if its light enough and functional enough for that ,its a boon to packing on a motorcycle.Campmor and REI are good sources

[birdrunner]

for camping,  any of the hiking type camp equipement.

For fixing the bike,  hockey stick tape .... Strong cloth material, sticks in the wet, lasts for years, and can be removed easily).  I use it to keep my wiring mess inplace.