The paint brush I am most familiar with is Castilleja chromosa(syn. Castilleja angustifolia var. dubia) found growing in the Great Basin high desert steppe comunities across the west.
There is some debate as to whether the correct name is "chromosa" or "angustifolia". I have given up changing the name. It doesn't matter what you call it, it's still a nice species.
I have had a little success growing it in the garden by scattering seed. I get a few to sprout and one or two have attached themselves to host plants. If they attach their roots to annuals they are goners by the end of the summer. I have one plant four years old that attached it's self to a Hebe cupressoides. It is on it's fourth year and though it has to grow up through the branches of it's host it gets bigger each year. I found a couple of young plants had spouted in my thyme lawn this spring. It will be interesting to see if they make it to maturity.

C. chromosa can be found blooming in a range of colors from vivid red through to bright lemon yellow. It is stunning to see plants with differant colored flowers blossoming next to each other. Large plants are about a foot tall and eight inches across. Most are half as wide. I have found it growing as high as 8500" on dry windblown crests. In those sights it is dwarfed to four to six inches. I do not know if it would stay dwarfed in more sheltered sights.
Here is a flikr sight owned by a gentleman named Mark Egger that is dedicated to the the Orobanchaceae/paint brush family.
http://www.flickr.com/photos/mark_egger_castilleja/collections/
Another link to the photo sharing group of Orobanchaceae
http://www.flickr.com/groups/orobanchaceae/

Now for the good part pictures!!