I've been wondering how the various companies that have CO2 offset programs do it; whether it's credible or not.
The climeworks program looks like exactly the kind of thing I'm looking for, however, so thanks for pointing that out. My CO2 emissions are on the order of 10 tons per year, going by the average per capita number, so that would be around $10,000 per year, with no tax deduction available (my marginal tax is 40%). Also, looks like their pilot plant sequesters 50 tons per year, corresponding to the output of five people.
But it's very much the right type of idea.
They seem to have changed their site, though, and I can no longer find the page that allowed a direct carbon offset donation.
Also, here in Oregon, you can pay the electric company a small fee (for me, about $11-12 a month) to guarantee that your electricity use is 100% offset by carbon-neutral generation (wind, solar, hydro, nuclear).
Also in Oregon, you can pay the natural gas company a fee (for me, $5.50 per month) to offset your natural gas usage with "bio digesters." I'm more skeptical about their efficacy.