HTC has launched a campaign to attract customers to its new flagship One handset with some serious money saving. "For One weekend only" in the US, HTC is offering customers as little as $100 and as much as $375 when trading in their old devices.

Specifically in the sale, the iPhone 5 brings in $300-$375, iPhone 4S $200-$255, Samsung Galaxy S3 $130-$210, Blackberry Z10 $250, Motorola Droid Razr $100-$184, LG Optimus 4X HD $150, and the Blackberry Curve and Blackberry Bold for $100. How much money you will receive will depend on the condition of the device.

HTC will offer the sale on HTC One handsets bought through AT&T, Sprint and T-Mobile during the sale weekend. Verizon is left out of the mix, with no HTC One in sight.

The trade-in process won't take place in the retail store, rather you'll have to visit HTC's "Trade Up" webpage and enter the promotion code "HTC100". You'll get a quote and shipping label to send it off.

We've given the HTC One a thorough review and found it to be one of the best Android handsets on the market. It is thought to be HTC's saving grace, bringing a serious unibody design to the table.

The sale runs from 2 May to 5 May, so if you fancy buying a HTC One, this might be the weekend to do it.