I took a cue from the backpacking community. They take everyday items (like spoons) and cut them down to make them lighter and more compact. So after a few attempts, and errors, I came up with a tool kit that is compact enough to fit into an altoids tin.
I've been using this kit now for 8 years and it has saved my butt, or a friend's at least five times. The tools are everyday tools that can be bought at any hardware store and the bike specific tools are readily available at any bike shop. The modifications are easy requiring only a bench grinder, a vise, and a hammer. If you have one, a dremal tool makes the job a bit easier.
Items needed ...
8 and 10mm wrenches, Open or Boxed
Hex wrenches 2 through 6mm
Two, 2-way screwdrivers
6 to 8mm adapter (if needed)
Park SW-7 spoke wrench
Park CT-5 chain tool
Other items if desired...
Glueless Tire Boots
Step 1: The Wrenches
Take the 10mm and measure 3-1/2 inches and for the 8mm measure off 3-1/4 inches. Mark with a felt tipped pen. Cutting the wrenches may be done in two ways. The easiest way is a Dremal tool with a cutoff wheel. The second requires the use of a bench grinder. "Score" an area about 1/4 of an inch above your marked measurement. Mount the wrench into a bench vise with the end to be removed above the vise jaws. Take a hammer and give it a good whack, the end will break off. Use the grinder to finish the end back to the marked line. Smooth the end so that it will be comfortable in your hand.
Step 2: The Screwdriver
Mark one of the shanks at a point 3-1/2 inches from the cross tip (+) and the second shank at a point 3-1/2 inches from the flat tip (-).
Cut the ends off with either the dremal tool, or the scoring methos mentioned under step 2.
Finish the ends as needed.
Step 3: The "Hex" or "Allen" Wrenches.
The only wrench in need of modification will be the 6mm. You need to make the long end short enough to fit into the Altoids tin. This step is easy, just use your bench grinder to trim back what is needed.
Step 4: Packing
Other items such as a presta-schrader adapter, glueless patches, and tire boots can also be fitted inside the tin as needed.