Wheelchair (Standard, Sports and Powerchair)
There is no official Lego minifigure-scale wheelchair (there is a Duplo-scale one), so I designed my own for my minifigure avatar (or "sigfig" as we call them in the AFOL world). Then I designed a couple more in honour of the 2012 Paralympics, culminating in a mini-version of my new powerchair.
I want these wheelchairs to get out there and into Lego displays and your own homes, so I made instructions for each design and am releasing them under a Creative Commons Attribution-NonCommercial-ShareAlike license.
Standard (Manual) Chair
The first standard (manual) wheelchair I designed for my sigfig. It's been refined a little over the years, but is basically the same. Instructions are avalable from Flickr.
One modification I didn't put in the instructions is a response to the colourful redesign of the Daleks in the Doctor Who series five (first Eleventh Doctor series) episode, "Victory of the Daleks".
Racing / Sports Wheelchairs
I'm not in the slightest bit sporty, nor do I even watch sport, but I couldn't resist the challenege of trying to build a racing wheelchair complete with angled wheels. Instructions can be viewed on Flickr (the non-racing version does not have instructions, it's just a minor modification to the racing design).
Powerchair (Motorised Wheelchair)
Finally, I got a powerchair at the end of 2012, so decided to upgrade my sigfig's chair too. Again, the instructions can be viewed on Flickr.
Have fun building your own Lego wheelchairs - if you build one, I'd love to see it.