Aerospace Bob has a great blog. Here's a recent thing he posted that I never know about.
Want to participate in a Space Mission? Stardust@home is a space science project in which volunteers from the general public help scientists locate particles from distant stars. The particles were captured by the spacecraft Stardust and are embedded in collector plates made of aerogel, which were carried by the spacecraft. The aerogel plates, and the particles within them, were returned to Earth in a sample return capsule on January 15, 2006. The purpose of Stardust@home is to find the particles within the aerogel plates. For more data, see this website.