These are pretty neat.
David Parkinson has designed hockey jerseys for each of the 30 MLB clubs based on their local NHL affiliate. So, for example, the Toronto Blue Jays jersey is based on the Toronto Maple Leafs:
And the New York Mets jersey is based on the New York Islanders:
Parkinson had to bend the rules a bit for some teams -- the Cleveland Indians jersey is based on the AHL's Lake Erie Monsters, the San Diego Padres jersey is based on the WHA's San Diego Mariners, etc. -- which is understandable.