Wyeast Brett B - 16%
Other - 14%
Wyeast Brett L - 13%
White Labs Brett C - 10%
Wyeast Brett C - 7%
Wyeast Brett A - 4%
East Coast Yeast Brett Blend #9 - 4%
White Labs Brett L - 3%
Brett Drie - 3%
East Coast Yeast Brett Blend #1 - 2%
Allagash Brett - 2%
It's great to live in a time and place where there are so many strains of Brettanomyces readily available (both from yeast labs and bottle dregs). Just like the Saccharomyces used by brewers, all of the available strains of Brett fall into two closely related species, but instead of ale (cervisea) and lager (pastorianous) they are funky (anomalous, which includes claussenii) and funkier (bruxellensis, which includes lambicus). Ale yeast is comprised of a huge range of different strains (think that Saison Dupont and Sierra Nevada Pale Ale are both fermented with it) in the same way within these two Brettanomyces species there are a wonderful variety of characters (so for example the strains that two labs market as Brett lambicus can be completely different from one another). There are also a few other species of Brettanomyces that are just starting to be used intentionally in brewing (there is B. custersianus in our Strong Golden Solera as part of the East Coast Yeast Bugfarm IV).
The way in which "new" Brett strains are developed is different from brewer's yeast. Most ale and lager strains are the result of slow mutation starting from another strain, usually at a brewery where long-term repitching under certain conditions and harvesting methods cause a mutated version of the strain to become dominant. With Brett, in most cases new strains are either discovered accidentally (as Allagash's Brett was in a batch of saison) or isolated from a wild fermented beer (Avery's Brett drie was cultured from a bottle of Drie Fonteinen J & J Oude Geuze Blauw). Now it is true that some Brett strains go through the same process as brewers yeast in the cases of breweries like Jolly Pumpkin and St. Somewhere who do not start over from a cultured strain (Lambic brewers fall into this category as well since cells live in the barrels waiting to work in the next batch along with whatever microbes happen to fall into the wort as it cools).
For the commercial strains, I tend to like the Wyeast more than White Labs in general (especially the WY Brett L cherry funk compared to the WL's full on funk assault), but my favorite is White Labs Brett C (which has just the right balance of fruit and funk for my tastes in most applications). It works well in both English and Belgian styles, and I've even had good luck using it in 100% fermentations. The Brett B strains are pretty similar with the Wyeast being slightly less aggressive in my experience. I had a chance to use the WY Brett A strain for a few beers before it was discontinued, but it was pretty similar to the WL Brett C with a bit more funk.
I'm looking forward to seeing how my first beer, a rye saison, with ECY Brett Blend #1 is when I bottle it next week. I also love dregs from sour beers, but they are harder to judge because you don't know exactly what cells are alive (I also like to use a few bottles in combination to ensure a variety of microbes).
I'm interested to hear what all of the people who picked "Other" wanted to vote for, I assume you weren't all going for the Brett strain Wyeast includes in their Berliner Blend. I didn't include other commercial breweries' cultures because for the most part they either have a house culture that is one of the ones mentioned, or that has mutated, but isn't controlled/banked/available I'd also like to hear any comments on what it is about your favorite strain that does it for you.