Zach Davis did a good job on his "colorless" pokemon list, but I, VGW Man, 
decided to go one step further. Not only did I include all of the pokemon 
that can use colorless energy from Base Set to Fossil (including the ones 
that didn't attack), but I also went all the way to Gym 1 (thanks Pokemon 
Patch & Apprentice).

The following pokémon can use any type of energy for at least one of their 
attacks. If they have a star (*) by their name, then their "attack" doesn't 
do damage.

Key:

BS-Base Set
JU-Jungle
FO-Fossil
TR-Team Rocket
G1-Gym 1

For Gym 1, I am assuming you know which gym leader owns what pokemon. Since 
there are many different versions of the same gym pokemon (I counted 3 
Erica's Bellsprouts), I also included the level numbers for the gym pokemon 
that had multiple personalities.

FIRE

BS Charizard (with Energy Burn)
BS Charmander
BS Charmeleon
BS Ninetails*
BS Ponyta
JU Flareon
JU Rapidash
TR Charizard
TR Charmeleon
TR Flareon
TR Rapidash
G1 Vulpix L10
G1 Vulpix L16*

WATER

BS Magikarp
JU Vaporeon
TR Magikarp
TR Squirtle
TR Vaporeon
G1 Goldeen L10
G1 Magikarp*
G1 Poliwhirl
G1 Psyduck L15
G1 Shellder
G1 Tentacool L12*

ELECTRIC

BS Pikachu
BS Voltorb
JU Electrode
JU Jolteon
TR Electrode
TR Magnemite
TR Magneton
G1 Jolteon
G1 Pikachu L10
G1 Pikachu L15*
Promo Electabuzz
Promo Pikachu (TCG League; not movie)

PSYCHIC

BS Drowzee
FO Slowpoke*
TR Slowpoke*

FIGHTING

JU Cubone*
JU Mankey
JU Rhyhorn*
FO Aerodactyl
FO Kabuto
FO Sandslash
TR Machop
G1 Geodude L13
G1 Graveler L32
G1 Mankey L10*
G1 Mankey L12*
G1 Mankey L14*
G1 Onix L41*
G1 Rhyhorn L25
G1 Sandshrew L13*

GRASS

BS Beedrill
BS Kakuna*
BS Metapod*
JU Exeggutor
JU Paras
JU Paresect
JU Scyther
FO Golbat
FO Grimer*
FO Zubat*
TR Ekans
TR Koffing
TR Zubat
G1 Bellsprout L15
G1 Exeggcute L12
G1 Golbat
G1 Zubat L10*
G1 Zubat L5*

If you have a problem with anything on this list, please contact me at 
vgw100@hotmail.com. I'll accept all kinds of email, but if you send me hate 
mail, expect to be blocked.