OK, my current set up:
Highlander down bag (good to 10deg)
3/4 self inflating mat
Alpkit bivvi bag
Army surplus poncho/tarp with para cord and 6 alloy pegs
Alpkit Ti mug
Spork
Triad meths/esbit stove
Fuel bottle
Matches
Wet wipes
Bio-degradeable soap
Mini tooth brush + tooth paste
Combe
Lens cleaner for glasses
Merino longjohns*
Merino longsleeve*
Merino socks*
Merino beanie*
Glove liners
Spare cycling shorts
Cycling jersey
Udderly smooth butt-cream
Sunglasses+case
Merino t-shirt
Zip-off trousers
Tool kit
First aid kit
Spare tube
Pump
Mini Gerber tool
Water purifying tabs
GPS
Maps
Fenix front light
Cateye rear light
4x lithium AA's
Arm warmers
Leg warmers
Montane Velocity jacket
Montane superlight over trousers
Sealskinz grippy gloves
2x 750ml bottles on the bike
On Me:
Normal cycling clothes
Ricoh CX1 camera and spare batteries in LowePro case over shoulder.
Thats for pretty much unlimited touring, for overnight stuff the casual clothes and extras would be ditched. It all fits in my Epic designs seat bag and Handlebar harness (sleeping kit in Alpkit drybag)
Total weihgt is c16 lbs inc water and 2 days of food. "race weight" is nearer 12 lbs.
Pic here
SSP
*excellent Chocolate Fish merino products