(Ben Claassen III/For Express) (Ben Claassen III/For Express)

How do you know you’re at a Halloween party in D.C.? At least two people are dressed as “Obamacare,” five are caked in orange face paint (a la John Boehner) and there’s a woman who looks just like a national security adviser. Wait, she might not be in a costume.

If you feel compelled to wear something topical, at least don’t be typical. Here are a few transportation-related costume ideas that will prove you’re up on current events but won’t make you look like such a jack … -o’-lantern.

Weekend MARC

Couples costumes are often barf-inducing. This one should cause nausea only in people prone to motion sickness. That’s because this getup celebrates the expansion of commuter rail service between D.C. and Baltimore that’s set to start Dec. 7. One of you is Mr. Boh (thick handlebar mustache, slicked-down black hair, one eye under a skin-colored patch) while the other is a Ben’s Chili Bowl half-smoke (reddish-brown unitard and face paint, tan coat, pockets stuffed with potato chips). Attach some kiddie model trains to your sleeves, and then hug all night.

Ridesharing

Getting into a car with a stranger sounds scary, but such services as Lyft and Sidecar — which turn regular drivers into pals willing to give you a ride — are actually pretty awesome. Kind of like Bill Cosby in “Ghost Dad.” (Just forget that in the movie he dies in a car crash.) Lyft makes sure folks can spot their cars by slapping giant pink mustaches on the vehicles’ grills. You can order up a similar one from carstache.com — Lyft’s official carstache purveyor — and simply affix it to whatever else you’re wearing. Worried the $40 model might be a little wide for maneuvering around a crowd? There’s also the $15 bikestache option. To complete the costume, take your sweet time when walking over to people and ask for a donation every time you hand someone a drink.

DC Streetcar

Curlers in your hair and slippers on your feet will indicate that you’re not ready yet. But that could work for any number of transportation-themed costumes — the Silver Line, the standardized taxi dome lights (required on all cabs by Nov. 1), the M Street bike lane. To help show that you’re representing the return of D.C.’s beloved streetcars, don a red outfit with a silver stripe down the side. Get some pieces of wire to stick straight up out of your hair. Also, keep explaining that although you’ll go all over the city eventually, you’re only willing to head to H Street for now.

Preschoolers clamoring to dress as Metro track workers, engineers or cops can order costumes for $36 each at dcmetrostore.com. Seriously.