Sometimes when you're browsing the web on the G1 phone, the link you want to click on is so small you can't actually click on it accurately. If this happens, you can use the trackball to click the link instead. Just use the trackball to highlight the link. Once it's highlighted you can click the trackball and it'll select the link for you just as is if clicked on it. If you hold down the trackball instead of just clicking, it'll open the context menu so you can do things like choose to open the link in another window, bookmark the link, etc.