Having an air compressor in your workshop is a necessity these days, especially if you have a tubeless wheelset.  But what you will quickly find is that all of the compressor tools are designed around schrader valves, not presta.  There are specialty companies that sell a presta tool, but they are expensive.

Digging around on the internet, I found a better solution that was much less expensive.

My solution requires 3 different pieces, bought at 3 different places.  While that sounds like a lot of work, they are places that I either go to all the time or are next to places I frequent (like Fry's), so there wasn't any wasted trips.  

To make this tool, you need 1.) a cheap schrader air gun, 2.) a schrader/presta adapter and 3.) a hose connector.

The first piece was a schrader air gun.  I chose a really cheap one at Harbor Freight Tools (yes, you get what you pay for, but this was an experiment). For $9 I was able to pick up a pistol grip inflator with a schrader attachment. This is a cheap product, but it serves my purpose.  Allegedly the gauge is not that accurate, but it seems OK for this purpose.

The second piece was picked up at Bicycle Sport Shop.  This is a replacement hose for a Specialized floor pump.  If I remember correctly, it was ~$10.  I am sure you can find other ones cheaper. If you have an old pump that might be the best solution.  

The final piece pulls the two together.  I picked it up at Lowes, but they probably have them at Harbor Freight.  This is a hose connector that allows you to connect the two hoses together, for ~$4.

Simply cut the schrader fitting off the end of the air gun, trim down the air pump hose to the right length and use the connector kit to hook it all together.  

All together the end product was about half the cost of buying a presta-specific unit, and while it is probably lower quality, it does the job.  With the Specialized head I can inflate either presta or schrader tubes, as well as my cars, so I get the most out of my compressor.