Some of my favorite duo chromes are:
MAC
Stars 'N' Rockets (iridescent pink and purple)
Gorgeous Gold (literally is a gorgeous gold with a teal/green duo chrome)
Vex (grey with pink duo chrome)
Smoke and Diamonds (Grey with green duo chrome--like a Japanese beetle I think)
Motif (Cream/yellowish with pink duo chrome)
Beauty From the Earth (BFTE)
Whisper (White with light blue Duo Chrome)
Mermaid (Yellow with Green Duo Chrome)
*Mermaid is very similar to MAC's Gorgeous Gold*
Kryolan
Pink Sunset (Pink with purpley duo chrome)
*Pink Sunset is very similar to MAC's Stars 'N' Rockets*
Have fun with Duo chromes and experiment!