Pay by the hour (time-billed)
The clock is running, and you are paying for every minute you're connected.
An open-ended meter earns more for every extra minute you stay, which rewards games built to be sticky and bills that grow without a ceiling.
What you're actually buying
Minutes of connection to someone else's computer, not the game itself. Charges ran by the hour (or minute), often on top of phone costs, for a persistent online world you had to be logged in to enjoy.
How it works
Before the web, going online meant dialling into someone else's mainframe. Operators such as CompuServe and GEnie paid for that computer time, and for network capacity leased from Telenet and Tymnet, so they billed you by the minute. Every extra minute online was pure revenue, so the earliest multiplayer worlds were built to be sticky, social and grindy. A game billed by the minute never needs an ending, only a reason to keep the meter running. Players logged on at odd hours to dodge peak pricing.
When it's fine
Rarely, and only with a hard cap or a fixed block of hours that you can see. Today it is mostly a historical ancestor of subscriptions rather than a model to look for.
Where it came from
MUD1, a text-based multiplayer world, was coded in 1978 by Roy Trubshaw (later joined by Richard Bartle) on a DEC PDP-10 at the University of Essex; CompuServe licensed it in 1987 and ran it as British Legends until 1999. Island of Kesmai, Habitat and Neverwinter Nights on AOL followed. In 1985 Island of Kesmai billed CompuServe subscribers $6 an hour at 300 baud (a slow connection speed) and $12 at 1200 baud: literally paying extra to play faster. CompuServe's base charge ran $5-6 an hour before telecom surcharges could add roughly $30 on top. GEnie reportedly charged far more at peak hours, which pushed players online in the small hours, and AOL's early-1990s plan bundled five hours into $9.95 a month, then billed $2.95 for every hour after. Flat-rate access ended the meter in 1996 (AOL announced unlimited access in late October 1996, rolling it out from 1 December), but the habits it created, persistence, guilds and the grind, became the design DNA of subscription and free-to-play games.
Historical prices and revenues are in US dollars at the time unless marked A$.
By the numbers
Island of Kesmai billed CompuServe subscribers $6 an hour at 300 baud and $12 an hour at 1200 baud in 1985.
CompuServe's base connect charge ran $5-6 an hour before telecom surcharges could add roughly $30 an hour on top.
AOL's early-1990s plan bundled 5 hours into a $9.95 monthly fee, then billed $2.95 for every hour after.
AOL announced $19.95 flat-rate access in late October 1996, rolled out from 1 December 1996.
Games that use it
No games in the database use this yet. Well-known examples: MUD1, Island of Kesmai, Habitat, Neverwinter Nights (AOL).
Related badges
Covered in Video Games & Money: Ep 7 · Time billed.