Bitcoin uses peer-to-peer technology to operate with no central authority or banks; managing transactions and the issuing of bitcoins is carried out collectively by the network. Bitcoin is open-source; its design is public, nobody owns or controls Bitcoin and everyone can take part. Through many of its unique properties, Bitcoin allows uses that could not be covered by any previous payment system.
Bitcoin tagging for businesses/nodes has been discussed on the tagging mailing list but maybe not yet voted on:
- payment:bitcoin=yes Bitcoin accepted as a payment method at the Point/Points of sale. 
- payment:bitcoin=no Bitcoin is not accepted.
- payment:bitcoin=interval Bitcoin is accepted only at certain times; the notation for opening_hours=* can be used.
- payment:website:bitcoin=yes   Bitcoin accepted through a business's website yes. If it is not, then choose no.
- currency:XBT=yes Bitcoins are accepted/dispensed.
- currency:XBT=no Bitcoins are not accepted/dispensed.
- currency:others=no Add this tag if all accepted/dispensed currencies have been added to the feature, all other currencies which have not been explicitly tagged are treated as "not accepted".
Please use currency:XBT=* instead of currency:BTC=*. In fact "XBT" is ISO 4217 compliant. Do not use currency=bitcoin.
Maps / Apps / Listings
-  Anita, 'payment:online:bitcoin=yes',Tue Aug 12 18:55:33 UTC 2014
-  Janko, 'payment:online:bitcoin=yes',Wed Aug 13 09:09:49 UTC 2014
-  Anita, 'payment:website:bitcoin=yes',Wed Aug 13 11:57:43 UTC 2014
-  Janko, 'payment:website:bitcoin=yes,payment:bitcoin=yes',Wed Aug 13 12:20:53 UTC 2014