I'm a big fan of D&D, been playing since I was a pre-teen, and I can't help but think of a variation of these chips that would pay direct homage to the game by using the iconic chromatic dragon colour scheme for the chip and variation of inlay art to incorporate the type of energy in the dragon's breath. True or past nerds will understand, and they happen to follow standard Vegas cash colours, too!
White Dragon $0.25 - cold (denom could be switched with blue)
Blue Dragon $1 - electricity (denom could be switched with white)
Red Dragon $5 - fire (a good workhorse chip)
Green Dragon $25 - poison gas
Black Dragon $100 - acid
White Dragon $0.25 - cold (denom could be switched with blue)
Blue Dragon $1 - electricity (denom could be switched with white)
Red Dragon $5 - fire (a good workhorse chip)
Green Dragon $25 - poison gas
Black Dragon $100 - acid