I'll take that one up. 2003, no doubt about it. I was on the edge of my seat for the entire Tour.
When he finally took off on Luz Ardiden, I thought - okay, this is the LA I remember. Then, he crashed. Then he got up and kept going, Then he almost crashed again - he's finished. Then he got up again and left them all behind, albeit with a bit of help from the Euskaltel boys - they ambushed Jan at the end and cost him some bonus points.
It wasn't over until Jan crashed on the final TT. And the fates would bring down rain on that day, turning what normally was a brute strength contest into an exercise in fine judgment. In the end, that Tour was won by the team - they covered LA until he found his legs. Actually, they were all won by the team - something Liberty Seguros is demonstrating right now.
There were moments in the other Tours - passing Jan in the 2005 prologue, passing Ivan in 2004 on Alpe d'Huez, 'the look' and explosion on Alpe d'Huez 2001, and the Armstrong-Pantani duels of the 2000 TDF. (I still don't buy that 'gifting' line on Ventoux - it wasn't given, it was won with a hard ride)
But 2003 stands out as the Tour I couldn't stop watching. Exciting. I don't blame LA for making some of the other Tours boring, I blame the other teams for not being more competitive.