[quote=Risewild]
The only problems I see with those suggestions are that dogs are not big enough so making a cyberdog (which is more than 50% actual dog) there is no way a human could ride one of those. The other problem is that there is no horse brains because horses are extinct.
Giddyup Buttercup toys were actually robots that were made so kids could ride them, still an adult human would not really fit well in one of those, but IIRC Mothership Zeta does have bigger Buttercups so I am sure there are different size parts around there too.

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[url=http://fallout.wikia.com/wiki/Gabe]gabe[/url] was large enough. And the mothership had things from several ages ago, such as a cowboy, if they were able to get cowboys they could get horses for sure.