The actress joined the Dragon's Den surviving company at its stand, Gallery 164.
She commented: "I'd all but given up on board games. About Time has reignited all that childhood excitement I used to experience all those years ago.
"What I love about this game is that even if you're a bit of an ignoramus (like me), you can still potentially win and along the way, will have learnt amazing facts that you can impress other people with.
"This games will take centre stage in my house for many years to come."
Costume characters of iconic revolutionaries, including Che, Martin Luther King, John Lennon and a gorilla, will also be seen walking around the fair.
The characters are carrying placards protesting that it is About Time for a new board game.