White Labs has done something that I have always been interested in. Yesterday, they opened a yeast differentiated tasting room. After brewing several batches of the same beer and then pitch a different yeast into each one allowing you to differentiate what a specific strain of yeast will do to a beer. They might have 10 pale ales each with a different yeast pitched and you can taste them all. There is a total of 35 different taps/beers on site.
Chris White (of White Labs) and Jamil Zainasheffs book YEAST: The pracitcal side to beer fermentation is a great book on the subject of yeast and depending on which strain you choose to pitch and dramatically affect the final product. You can see a live list of what is on tap at their website.
I have wanted to do this type of experiment for a long time. My method would most likely be a little different though. I would most likely brew a single 10 gallon batch and then split it into four, three gallon carboys each with a different yeast strain. Since I neither have the glassware for this or the space this will probably not be an endeavour that I undertake anytime soon.
I may split a batch into two different five gallon carboys in the future just to differentiate between two strains. I really like the California Ale (WLP 001) and have been using the San Diego Super Yeast (WLP 090) recently because it is supposed to be similar just rapid fermenting. I may decide to split a batch with those two strains just to see what would happen. This being a low risk, low overhead proposition it seems right up my alley.