Similar to Acid3

.tl

.tn

.to

.tokyo

.tr

Transifex

Tripod (web hosting)

.tt

Tumblr

.tv

.tw

Typepad

.ua

.ug

.uk

Uniform Resource Identifier

Urchin (software)

.uy

.uz

.vc

.ve

.vg

Virtual private network

Visual.ly