Just a plea - remember that there is a tier between "freeloaders" and "companies willing to pay $$" - it's what you would call the "supporter" level. This is the level that dropbox, for example, lacks - some ability to give, say, $3 a month not in order to get premium features, but to feel good, and support a product you like.

I use Trello every day for a whole bunch of things and it really does make my life easier. It would make me happy to give Trello a bit of money for services that I already use for free.

[Edit to comment below: I don't think it is such a strange suggestion - it's the NPR model: everybody gets to listen to the radio station for free, some get to feel good about supporting it in exchange for something nominal like a bumper sticker. Sure there is a difference between accepting money and never having to deal with money, but I assume Trello has some plan to accept money eventually for something]