We have seen a few great Windows Phone 8 deals recently, but I think the HTC 8S may take the cake for the cheapest yet.
Telstra is offering the handset on Pay as You Go for only $129 Australian ($125 US). While the handset has the same basic specs as other devices in the price range (512 MB RAM, no front-facing camera, only 4 GB of storage) at this price it is cheap enough to buy for a teen or to keep in the glove box, making those issues much less relevant.
See the deal at Telstra here.
Thanks Brent3000 for the tip.