Video: The iBOT mobility system was a stair-climbing wheelchair that could also turn into a Segway. And sadly, it no longer exists.
As of 2009 the iBOT was no longer available for sale, and support for existing units was dropped about three years ago, mainly because these things cost $US25,000 ($34,398) each and US Medicare only chipped in a pittance.
That said, the Transformers-like process from wheelchair to Segway has all the heart-skipping elements of accidentally falling over backwards, which might have contributed to its meagre sales.