Wow! The bandwidth charges in Canada are crazy! I've had a hosting service for about 10 years (mostly for play and testing). I pay $5/month now...so it sounds you've got costs under control.
I'll just throw this idea out as an idea. A friend of mine started the site at this url,
http://www.ajaxonomy.com/, a couple of years ago. He added "Ads By Google" to his site. I just took a look at the site and the actual ads occupy a small amount of space. I asked recently how much revenue this collected. He told me about $100/yr. This is more than enough in his case to pay of the hosting expenses. He said he was going to need to take to lunch the others who contribute to his site because he has collected too much money.
