Facebook now has a new feature that lets you upload your photos to Facebook using email. To use this feature you need to log in to Facebook and go to the mobile page at http://www.facebook.com/mobile/. You'll see a section of the page that looks like this:

Facebook mobile page showing the section that specifies your custom email address for uploading photos.

The section outlined in red (it won't have the red in Facebook) shows an email address that is unique to your account. Do not share this address with anyone! You can send photos to this email address and they'll get posted to your profile. If you want to caption the photo, include a subject in the email and the subject you enter will be used as the caption for the photo.