This is an interesting idea. Looks like it might be more useful than a standard tractor.
TV145 Bidirectional™ tractor
<img src="http://www.newholland.com/na/news/PowerManager/Issue53/PMnpn_1.jpg">
TV145 Bidirectional™ tractor
<img src="http://www.newholland.com/na/news/PowerManager/Issue53/PMnpn_1.jpg">