Amex Digital, who make a variety of home entertainment and HTPC kit, have just announced this, the iMON HD Mobile. Billed as a portable media center, it seemingly comprises a VFD display and IR receiver (with bundled remote) that can control all manner of media software. It'll also display email, news and weather information.
However, it's entirely unclear whether this is an actual media streamer or just a wireless display and control system. The former would be useful, whereas the latter would be a whole lot more unnecessary considering you'd just have to route video from your computer to your TV in some other way. Sadly Amex Digital are obviously too busy collecting compatibility logos to update their site with any usable detail.
I've got a request in with them to hopefully find out more, but until then this is a suspend-judgement device. I'll update this post if/when I hear back.
Update 5/18: Amex Digital have pointed me in the direction of their well-hidden press release, which confirms that this is merely a USB-powered display which can relay IR signals from a remote control back to your HTPC. You'll still need to connect your PC to the TV in some other way; the iMON HD Mobile is not a media streamer. It's available now, priced at $59.
[via Akihabara News]