Here are some of the rat varieties that are out there. Color wise I may be missing some I'm sure. If anyone wants to add on to the list just send me an email.

Agouti Based Colors
     Agouti
     Fawn aka Topaz (Agouti + RED)
     Amber aka Silver Fawn (Agouti + PED)
     Cinnamon (Agouti + Mink)
     Cinnamon Pearl (Cinnamon + Pearl gene)
     Russian Blue Agouti (Russian Blue on Agouti)
     Russian Cinnamon (Russian Blue + Mink on Agouti)
     Russian Silver Agouti (Russian Blue + American Blue on Agouti)
     American Blue Agouti aka Opal (American Blue on Agouti)
     Russian Fawn (Russian Blue Agouti + RED (Beige)
     Platinum Agouti (American Blue + Mink or RED on Agouti)
     Havana Agouti aka Honey Cinnamon (Cinnamon + RED (Beige)
     Silver Agouti aka Apricot Agouti (Am. Blue + PED (Champagne) on Agouti)

Black Based Colors
     Black
     Beige aka Buff (Black + RED)
     Champagne (Black + PED)
     Chocolate
     Cocoa (Chocolate + dilutes esp. Chocolate carrying RED (Beige)
     Russian Blue
     Russian Dove (Russian Blue + Mink or Chocolate dilute)
     Russian Silver aka Silver Blue (Russian Blue + American Blue)
     Russian Beige aka Blue Beige (Russian Blue + RED (Beige)
     Russian Champagne (Russian Blue + PED)
     Russian Pearl (Russian Blue + Pearl)
     American Blue aka Blue or Slate Blue
     Sky Blue (American Blue + modifiers)
     Powder Blue (American Blue + modifiers)
     British Blue (formerly UK 'English Blue' and shown in US as Blue)
     Platinum (American Blue + Mink or RED)
     Platinum Pearl (Mink-based Platinum + Pearl gene)
     Pearl (only displays on American Mink)
     Silver (American Blue + PED)
     Lilac (American Mink + Russian Blue or RED)
     Classic Lilac (Chocolate + American Blue or Mink may carry Beige)
     Lavender
     Mink
     Mocha aka Havana (Mink carrying RED (Beige)
     Coffee (Chocolate + Mink)

Other Colors
     Albino aka PEW
     Black-Eyed Cream (Black-Eyed gene + Albino gene)
     Triple Dilute (3+ recessive genes on a single rat)
     Silvered (Silvering appears to be recessive)
     Black-Eyed White aka BEW (PEW + Black eye gene)
     Roan aka Husky

Color Points
     Himalayan (Albino gene + Color Point gene)
     Black-Eyed Himalayan (Black-Eyed gene on a Himalayan rat)
     Seal Point Siamese
     Russian Blue Point Siamese
     American Blue Point Siamese
     Mink Point Siamese
     Black-Eyed Siamese (Black-Eyed gene on a Siamese rat)
     Burmese
     Sable Burmese
     Wheaten Burmese

Markings
     Self
     Berkshire
     English Irish
     Irish
     Banded
     Varigated
     Dalmatian
     Hooded
     Bareback
     Capped
     Masked
     Blazed
     Cap/Stripe
     Patched
     Downunder Berkshire
     Downunder Hooded
     Downunder Varigated
     Essex
     Baldie
     Badger
     Possum
     Collared

Coat Types
     Standard/Smooth
     Rex
     Velveteen
     Double Rex
     Hairless
     Satin
     Harley

Ear Types
     Standard
     Dumbo

Eye Types
     Black
     Ruby
     Pink
     Oddeye

Tail Types
     Standard
     Tailless

Body Types
     Standard
     Dwarf