Perhaps, like me, you’re tired of hearing all the post-inaugural replays during this morning’s news. (Personal opinion: the world doesn’t need to hear Alicia Key’s rendition of Girl on Fire anymore, but this is a rare occasion to link to Perez Hilton so if you want to see it, you can give him, not Politico, the web traffic.)

And perhaps, because, if you’re like me, you were paying attention only to Martin Luther King Day, and the presidential inauguration, you missed some business news that happened over the weekend. Here’s what’s going on with two Chicago-based companies today: Boeing and Groupon.

Japanese and American investigators are traveling to Kyoto and Arizona, respectively, in their separate quests to find out what went wrong in Boeing’s 787 Dreamliner fires that have grounded the aircraft.

Japanese investigators are looking into Kyoto-based GS Yuasa - a battery maker that dates back to 1895, when it created Japan’s first lead-acid storage battery - to see why the batter overcharged and caught on fire.

The National Transportation Safety Board said on Sunday that the fire in Boston was not overcharged, but that there could be problems with wiring, circuitry or other components. So it is looking into the Tuscon, Arizona-based Securaplane, which provides some elements of the battery system.

In the meantime, Boeing’s 23,000 engineers and other professional workers have been working without a contract for a few months now. The union rejected the company’s latest offer last week and now are considering the possibility of asking its members if they want to strike. Expect that news later today.

Groupon, meanwhile, said yesterday it was reviewing all of its deals involving guns. That’s angered some gun shop owners that had pending Groupon deals, like this Austin-based owner who is now saying everyone should boycott Groupon.

Here’s the story from Austin NBC affiliate KXAN:

Gun shop owner criticizes Groupon’s ban