Roller skates, like freight trains and time, mostly travel forward, sometimes backward, and rarely sideways. Explore temporal transportation with today's Groupon: for $9, you get admission and skate rentals for two at Tarry Hall Roller Rink in Grandville (up to an $18 value). Public-skating sessions take place Fridays from 7:00 p.m. to 10 p.m., and Saturdays from 1:30 p.m. to 3:30 p.m. and 6:30 p.m. to 9 p.m.

Tarry Hall Roller Rink's oval arena eschews the boredom of walking in favor of whimsical wheeling, setting an ambient backdrop of groovy tunes to complement the sweet sounds of plastic on wood. Take to the rink for public-skating sessions on Fridays or Saturdays, set to the sounds of rock, oldies, and auto-tune recordings of phone-book prose read aloud. Available for temporary taking are 350 pairs of skates, 120 pairs of rollerblades, and a single broken pair of antigravity sneakers. A snack bar offers solace for those who left it all on the floor, unless that includes their wallets.