Black, red, and blue.

Green.

Silver.

blue and black

Orange, pink and violet. Ducky yellow, too. :3

breen

Red.

black

Powder blue, a deep indigo, and a royal purple make a nice matching set. Possibly bubblegum pink as well.

You're likely to get every color imaginable.
That been said, Green and Orange are nice. Not together, though.

every other colour not yet mentioned, too. :) you have 16.8 mio colours available, right? so, there. :P

I'm gonna go with bubble gum pink.

Silver, light blue, and red.

Purple Green and Blue

Red, purple, pink, greens... All o' them really. ^..^ Balloons rule!

Blue and purple.

Depends. For random radiosondes and the like, something blaze-orange that stands out when you're tracking it with a surveyor's transit. For critters...just match the basic concept of the creatures coloring and try not to go for the loudest colors out there.

(Think of me doing that stegosaurus drawing (ask Tombfyre) in chartruese and blaze-orange. That would be decidedly...painful, right?)

Black And White.

the're all good

All of 'em, but I will confess to a certain fondness for pink. :)

marble-mixtured red, black, beige, light blue, royal purple, white and gold