Remember when Ted Leonsis was really excited about the Washington Capitals browser theme about 5 years ago? The Washington Nationals have caught up and now offer a browser theme as well.
Like all BrandThunder browser themes, there is a toolbar with links to the team and league sites, tickets, social media, headlines, etc. There doesn’t seem to be a link to the shop, though which seems very un-Lerner like.
I don’t know how many people use browser themes, but I still a “derp, we have a team” type of fanboy that I have installed it. When the Caps are in season, I tend to use that one too. They wind up making your browser really, really red though.
Most of MLB seems to be represented and so is D.C. United.

