simplenet.com has a long history, but a couple years ago they freed themselves from yahoo's corporate grip (one of yahoo's dumber moves, imho, but it did serve as the foundation of their 'yahoo domains' hosting.. which btw, is a nightmare, but that's yahoo's fault, not simplenet's).
instead of the traditional 'bulk' reseller plans, where you buy XX amount of resources and set up clients inside of that; you create completely custom packages (down to the megabyte of disk space), based on their wholesale rates for each resource. you get your price for the package from simplenet and mark it up accordingly.
the nice thing about that is you don't have to worry about squeezing another customer into your reseller space, everyone gets their own resource allotment; and built-in to the package pricing is amounts for overages... not counting the $75 reseller account setup fee; you can *always* clear a profit on every account sold, even on the very first one.
they don't have a bazillion gateways or registrar hooks available (authorize.net and enom, i think, are what you can use for those).. but they have a pretty nice control panel (proprietary); and aside from the pre-yahoo, 'all you can eat' issues with sites getting shut down or charged extra because they did use 'all they could eat'... they are, and have always been, a pretty solid host.
anyone use their reseller program care to comment on the experience with them?