The LG G3 flagship only just arrived in the US and it already has $100 cut off its on-contract price. The phone is available on AT&T, Verizon and Sprint, the three of which offer it at $200.
Best Buy and Amazon, however, have dropped the upfront price to $100. Note that this is for the version with 3GB RAM and 32GB built-in storage. All three carriers have the Metallic Black version, AT&T and Verizon also have Silk White while Sprint offers Shine Gold.
Best Buy's web page doesn't mention it but apparently you can get $100 in-store credit if you pay for the early upgrade program of your carrier of choice - AT&T's Next, Verizon's Edge or Sprint's Easy Pay.