Strawpoll – an open alternative to closed SRS?

I’m thinking that it would be a fair guess to say that in a typical university classroom, 90% of the students in a large class will have a phone – with a text plan – so if you can get them to get a twitter account, or if they have neither, get an account add a phone with a text plan, you might be able to get all the advantages of SRS with non of the administrative overhead by setting up a Twitter StrawPoll. Granted, you are not going to be able to get the same manner of stats and I don’t think you’ll be able to do assessments with this, but it’s certainly a start into the world of SRS.