Here's a list.

Here is a link that might be useful: Acid loving plants

Used coffee grounds do very little to acidify the soil. They are a great soil amendment, but don't look for them to lower the pH. They are very close to neutral.

I use the Starbucks grounds but only because they are free. They do fine as a soil amendment around any plants, but like rhizo says, they don't do much to acidify the soil.

See the bottom of this page for a discussion of the pH of coffee (it doesn't go into the pH of the grounds themselves).

Here is a link that might be useful: pH of coffee

One more thing - caffeine is poison to slugs, so keep using that leftover coffee and grounds in the garden!

I agree with rhizo, a whole lot of coffee grounds are not going to change the pH but possibly a little bit and you can neutralize this with a tablespoon of lime. I sprinkle it around ALL my plants and even add it to my compost pile and potting soil mixes. I think this is a good thing Starbucks is doing so I wrote about it on my blog.

Here is a link that might be useful: click on BLOG

Coffee grounds are great for making compost too, along with whatever other vegetable waste you have, grass clippings and of course leaves in the fall. If you want to get hooked on composting, go to the Composting Forum. It's a hoot.

I overdid it with my compost and smelled terrible and didn't cook well so don't overdo the coffee in the compost.