These tubes are cool because you can change a tube without removing a wheel! Velomobile describe the tube thus:
Rather than having a full anulus as in a normal inner-tube the Cobra is a stright (sic) length of tubing sealed at both ends with a small loop allowing the both ends to be joined into a circle at the valve point. I was not aware of the product before, but in hind sight it is really obvious and goes to show how one’s thinking can easily be limited by just doing things the way they have always been done.
As Velomobile suggest, these are particularly cool for velomobile owners but I do think the potential goes well beyond velomobiles if larger sizes are offered.
To see how the Cobra Linear Inner tube works, check out this video on Vimeo.