Please read the comments for some shades of meaning about the whole question.
JustVolunteers.org is a new volunteering matching site run by NY Corporation Baou, Inc.
It offers what they call “Virtual Opportunity”.
Would I recommend it? nope
Why? Go there and try if you can find anything of your interest.
Error #1: “virtual” is not a category, but a channel. I mean, my profile is not a choose amongst Politics, Environment or Virtual Opportunity. I might be interested in volunteering for the environment even if I wanted to do it virtually.
Thus, this category is a complete mess.
On the other way, error #2, we should start building a consensus on what we call online volunteering. I once draw four types of online volunteering. People usually stand on the first type (Advocacy) while I’d prefer 3rd or 4th (real online volunteering). So, we’ve got a problem here. No matching site will work until we solve, at least, these two big errors or, at least, we make up something to keep everybody within the same framework and discriminate different definitions.
My opinion, of course ;)