From Envirowiki

Consider this: Lots of people give $5/month to various environmental organisations. But $5 is less than half an hour's work on a living wage in a developed nation. So if you spend an hour a week doing some environmental advocacy work, you're really donating more than ten times that, especially if you consider that most people aren't paid the full value of their work (the rest goes to the boss).

Currently, Envirowiki would much rather if you donate your time by adding content than by working to give us money. That's because we don't really need money, but we really need content. If you're stuck for places to start, start with your local campaigns, or check out the Wanted Pages for pages that Envirowiki needs. If you're stuck on formatting issues, you can check out the help pages, or start by editing an existing page, and figure out the formatting from there.

[edit] Financial donations

Envirowiki doesn't have any major expenses. We pay about $20/year for our domain name, and we get hosting free from enviro-geek.net (naught101, the founder of envirowiki, helps run enviro-geek.net). Such hosting would probably cost us about $60/year at normal rates. If you feel like it, enviro-geek could always take donations.

Your other option is to donate to a local grassroots environment group. Smaller groups are often able to do and say great things that the larger groups can't, because of their large financial membership base that they don't want to scare off. A good rule of thumb is the more radical and active, the better, since there are already heaps of people saying the mainstream stuff), and it gives the Overton window a bit of a shove. Again, the logic at the top applies - your local group would benefit more from you doing a little volunteering than from your money.

If you do give money, consider what is more valuable: a small, constant donation (few dollars a month) allows the group to pay for things like printing costs, but if they start getting to much they may become reliant on your donations. A large, one-off donation will always be appreciated, and might be used for something that's harder to do on a tight budget, like buying equipment.

Do not donate conditionally. Collectively, the group probably has more experience than you, and will know where to put the money to best use.