Current Status
Sadly unofficially dormant, for the foreseeable future. A documentation error was discovered, going back to July 2007, with many potentially very complicated knock-on effects which would need to be recalculated. Though PTomic is not officially on hiatus, no Moves have taken place since the discovery, and there appears to be a consensus not to continue PTomic. Instead, a new Nomic has been started, based on the last supposed known rule set of PTomic. This Nomic is called PTwomic.
The Players of PTomic also started another new Nomic, before they decided to start PTwomic. It is based on an initial ruleset similar to the Regular Ordinances of FantasyRulesCommittee, and is called aPTomic.
History
PTomic (pronounced to rhyme with 'Nomic' and to alliterate with 'pterosaur') is a forum-based Nomic played in the Paradise Towers section of the Doctor Who Forum. It started on 25/11/06 18:27 GMT, with an Initial Ruleset based on the AgoraRuleset, the most notable differences being that voting was non-secret, and all Rules were mutable. (Both of those differences persist to this day, except that some Rules are now more mutable than others.)
A Sketch of Current Rules
PTomic uses fruit as a currency and is, to a great extent, played on a two-dimensional surface ('the Board'). The Board has the ever-changing topology of a demented doughnut that's suffering from worms and leprosy, and is populated with various things; including the Players, some horses, a Dalek, a Zombie, a Knifebearer, and the Rules themselves, which act as obstacles. Every object has a size, and too much size can cause bits of the Board (and their contents) to disappear (as can the Knifebearer). A game of Go is starting to develop, using the Rules as stones. PTomic cannot be won.
For the complete Rules, see the pages on 
Player-controlled and automatic game-events.
How to Join
PTomic is open to all members of the Doctor Who Forum. To join PTomic, simply click on the link below for the Thread, register with the forum if you've not already, and post a request in the Thread to join the game.
Latest Poetic Record
With a knife one came across To a cell where a being was Won a duel and took the spoils Of all the being's wordly toils And though not moved since game's begun That being now seems back at cell one Like willow tree with branches bent Face turned down in sad lament Of oranges and beans unspent And sculptures joyous to invent Of rules not made to regiment In Go! but now all gone.
Latest Acronymic Aphorism
Suber understood: Rules entwine in terrifying dances of everlasting subtlety.
Latest Referendum:
Lately, we've been voting on Three Deciduous Forests.
Web Pages:
PTomic Thread : The Thread in which the game is (mostly) being played.
PTomic Wiki : Links to the current Rules, and various game data.
PTomic Initial Ruleset : The Rules that PTomic started with.