Here are some randomly selected joke topics beginning with the letter 'T'
Terrorists
Last year a group of terrorists hijacked a planeload of lawyers. They said that they'd release one every hour unless their demands were met.
Terriers
How did the Scottish dog feel when it saw the Loch Ness monster?
Terrier-fied.
Terrific
If work is so terrific, how come they have to pay you to do it?
Termites
Termites are boring
Tense
Why was the mummy so tense?
He was all wound up!