Marcus is great on the radio. I imagine his written style is easy to read. Didn't he write 'The Nothing That Is'?
Google suggests that was Kaplan. But thanks as I hadn't seen that book...
du Sautoy did the Royal Institute Christmas Lectures in, umm, 2006. Somewhere round here I have part of it on DVD thanks to my dad (another maths geek). Ah, yes, it was obviously a maths night on TV:
9.05 Go Forth And Multiply (Ethiopian Multiplication)
9.10. The Music Of The Primes (du Sautoy)
10.10 The Life Of Phi (da Vinci/Fibonacci)
10.15 Breaking The Code (about Enigma)
11.45 Dreaming The Impossible (about Escher)
11.50 Horizon (Fermat's Last Theorem)
[EDIT] Random fact: In the same evening in Cambridge (Carols at King's no less) I saw both Andrew Wiles and I was almost run over by Hawking.
Gödel, Escher, Bach: an Eternal Golden Braid by Hofstadter is lying around somewhere although it takes a while to digest it...