Well I was browsing this video site called guttamind.com and found a nice & curvalicious tied-up DiD in an episode of this web animation shorts series called
Gundarr. Turns out there is a whole bunch of episodes and they're all listed on this page:
http://www.youtube.com/playlist?list=PL ... e=view_all" onclick="window.open(this.href);return false;
The eps look to be loaded with scantily-cad voluptuos women, and I'm sure there's more DiD.

The ep I saw was called "Meals on Heels" but there's definitely more tied up DiDs in this at least as the preview cap for #7 shows a different tied chick.
It's a little hard for me to check the rest of these today, but I'll probably dl all the eps at some point. In the meantime if you guys find anything more in these please share!