Marketcircle, the creator of my two favorite time billing and invoicing applications is donating the proceeds of all their Billings and Billings Touch sales to Japan’s tsunami and earthquake relief. If you’re not familiar with either of these apps, and you need a time billing and invoicing application, I highly recommend these apps. You can find out more info about what Marketcircle is doing on their Together we can help Japan blog post.
If time billing isn’t your bag, check out Macworld’s list of all the software developers who are donating proceeds of their sales. I’m sure there’s something useful out there for you.