Meet Jerry. Jerry appears to be some sort of weiner dog, and he also really enjoys playing fetch.

Jerry enjoyed playing fetch so much that his owner actually built a machine that would throw balls for Jerry, and that Jerry could work all on his own. 

Jerry's owner says that he built the ball machine he thought Jerry might like it and that it would be something fun for him to build. After two years of on and off work, with many safety features such as IR proximity sensors to protect Jerry and his son from the machine, he finally finished it. And it's awesome.

This machine surely didn't serve as a replacement for Jerry's owner, though. He says he ended up throwing balls for Jerry far more than Jerry used the machine.  According to the computer on the machine, Jerry only played with the machine by himself three times in his life.