Ceramique Designs
Many high-end speaker builders use Thiel units. This page gives an overview of some designs.Commercial designs
There is an increasing amount of companies applying Thiel units to their designs. Here is an (obviously non-complete) list:
Lumenwhite
Marten Design
Usher
Kharma
Venture
Isophon
Margules
Akkus
Mutine 
Talon
Jas Audio
In Stereophile some tests can be seen of the Marten Design Coltrane, the Lumenwhite, and the Kharma. From the curves, it is obvious that the frequency response is not totally equalized. Especially the Lumenwhite has a significant deviating response, with a lot of dips and peaks. This probably gives a very responsive, airy and fast sound, but with lots of resonances and difficult to focus stereo image.
[Stereophile, Marten Design Coltrane, 2/2005]
[Stereophile, Lumenwhite, 10/2002]
[Stereoplay, Lumenwhite]
DIY designs
Thiel units seem to have quite some attraction to the DIY community. I guess their differentiating ceramique technology, their high price, and the fact that these units are used by high-end speaker companies attract many people.Chorda
The Chorda from Hobby Hifi uses quite some compensation circuitry to get a flat response from the C^2 220 over a wide range. The enclosure is 60 litres, and has a vent of 100 mm and a length of 350 mm.
The filter is a parallel filter. The values of the woofer section are:
L1 = 2.2mH 2.0mm air-core
C1 = 15uF MKP, R1 = 8,2 Ohm
C2 = 8.2uF MKP, L2 = 3.3mH 1.0mm air, R2 = 15 Ohm
C3 = 8.2uF MKP, L3 = 0.22mH 0.7mm air.
DIY TLS
The response curves shown of the DIY TLS design differ a lot from my own. I tried to contact the author, but so far I haven't received a response, so I have no clue about the backgrounds.
Pure
The Pure is probably derived from the Kharma, and is based on a combination of series and parallel filtering developed in cooperation with Tony Gee. The crossover frequencies of the C^2 79 are at approximately 300Hz and 2.5kHz.next ->