I'll kick this off, give you some background info first because choosing a good host is important.
Ive been hosting websites for a few dozen web developers for over a decade.. Was doing it all manually as I never was satisfied with any of the control panel options, until my customers started demanding a direct configuration interface.
After writing a simple one managed entirely through a shell I started playing with ISPConfig3 and was so immensely impressed I went through and deployed an entire new hosting environment, and after alot of testing on it and several redesigns I moved all my customers over to it and they have been nothing but pleased with the results.
Everyone has been running great on the new system since June 2011, so I decided to expand my offerings and services to the public a few months later.
Currently I am offering 2 basic hosting packages starting off at $1 for the first month, these include full featured shell accounts with each site. (More Info
On top of that I offer Free Personal Web-hosting w/2GB Storage 1 Domain & Shell Account w/50GB Transfer for a one time setup fee of $1 (More Info
View our current hosting packages @ http://hostap.net/webhosting
-Ryan @ HostAP.net
I think creating a directory of ISPConfig powered hosts is an *excellent* idea, promoting a large verifiable install base will attract more 3rd party vendors into supporting ISPConfig IMHO.. so please, post up your site.