As fontes tipográficas mais usadas na web

Twitter – Pico Alphabet (Modificada)
Digg – FFF Forward (Modificada)
Cork’d – Triplex
Vimeo – Black Rose
Grooveshark – FF Nuvo
Envato – Agenda Italic
Tuts+ Network – Lubalin Graph
Last.fm – National (Modificada)
Technorati – Neo Sans Medium
Flickr – Frutiger Black
Purevolume – Avenir Book
Youtube – Alternate Gothic No. 2
Basecamp – Whitney
Facebook – Klavika (Modificada)
Engadget – Engadget Font
Google – Catull BQ
Yahoo – Yahoo Font
Hulu – Futura MDd BT (Modificada)
Bebo – Neuropol (Modificada)
TMZ – Amelia
The ONION – Eagle Bold
Mapquest – Cheap Motel
Linkedin – Myriad Pro Bold
Skype – Helvetica Rounded Bold
Revision 3 – VAG Rounded Black

Fonte: Build Internet