Because ephany demanded it, here's a reasonably comprehensive list of comic book shout-outs in the most recent episode of Smallville:
- Bart dresses in red and yellow, which historically have been the colors most frequently associated with the Flash and other DC Universe super-speedsters.
- Bart has a yellow lightning bolt on his backpack. All three of the Flashes have worn costumes with a yellow lightning bolt on the torso.
- The names on Bart's fake IDs -- Jay Garrick, Barry Allen, and Wally West -- are the secret identities of the first three Flashes.
- In the comics, Bart is the grandson of the second Flash, Barry Allen. Apparently, super-speed is inheritable, even when the power is an acquired characteristic. Comic book genetic science is fun! He used to be known as Impulse, but he now goes by the name Kid Flash.
- Bart tells Chloe he's from the future. In the comics, Bart was born in the 30th century but now lives in the present. Take my word that there's a reasonable explanaiton for it.
- A thug says to Bart, "let's see if you're faster than a speeding bullet." Technically, that's a shout-out to the old Superman radio show, but close enough.
- Bart says that if he finds any other kids with super-powers, they could "start a club or a league or something." Superman and the second and third Flashes were all members of the Justice League.
Plus there's all the usual Superman stuff.