Bellwether Hang out on the new queue and flag carefully
Well-rounded Post good links and good comments
Best Link Submit a great link
Best Comment Write a great comment
ComboLinker Submit lots of good links
ComboCommenter Post a high percentage of good comments in one day
Inciteful Link Submit something worthwhile but provocative
Inciteful Comment Write something interesting but provocative
Shutterbug Contribute a photo to the sidebar
New User Join Reddit!
Verified Email Address Verify your email address
Gilding (tiered) Gild a link or comment
One-Year Club Keep up the good work!
Two-Year Club
Three-Year Club
Four-Year Club
Five-Year Club
Six-Year Club
Seven-Year Club
Eight-Year Club
Nine-Year Club
Ten-Year Club
Eleven-Year Club
Twelve-Year Club

There are also some special trophies that are more rare than awards:

Translator Foreign language translations
Open Sorcerer Contribute code to reddit
White Hat RESPONSIBLY probe and report any holes in the reddit code. More details here.
CSS Animal Mysterious
Artisan Artistic contributions
Beta Team Participate in a reddit beta.
reddit Gold reddit supporter. More details here.
reddit Mold April Fools 2011 More details here.
Charter Member Joined reddit gold during the initial "no features yet" leap-of-faith period
Alienator Design a logo used on reddit's front page.
Team Orangered Emerged victorious in the great Orangered/Periwinkle clash of 2013
Team Periwinkle Fought valiantly in the great Orangered/Periwinkle clash of the ages