Something else that came up at OpenTech; is there any way of getting continuing information out of the government? This is especially interesting in the light of things like Who's Lobbying? and Richard Pope and Rob McKinnon's work in the same direction; it seems to me that the key element in this is getting information on meetings, specifically meetings with paid advocates i.e. lobbyists. Obviously, this has some pretty crucial synergies with the parliamentary bills tracker.
However, it's interesting at best to know who had meetings with who at some point in the past, just as it is at best interesting to know who claimed what on expenses at some point in the past; it's not operationally useful. Historians are great, but for practical purposes you need the information before the next legislative stage or the next committee meeting.
I asked Tom Watson MP and John "not the Sheffield Wednesday guy" Sheridan of the Cabinet Office if the government does any monitoring of lobbyists itself; you'd think they might want to know who their officials are meeting with for their own purposes. Apparently there are some resources, notably the Hospitality Register for the senior civil service. (BTW, it was a bit of a cross section of the blogosphere - as well as Watson and a myriad of geeks, Zoe Margolis was moderating some of the panels. All we needed was Iain Dale to show up and have Donal Blaney threaten to sue everyone, and we'd have had the full set.)
One option is to issue a bucketful of FOIA requests covering everyone in sight, then take cover; carpet-bomb disclosure. But, as with the MPs' expenses, this gives you a snapshot at best, which is of historical interest. As Stafford Beer said, it's the Data-Feed you need.
So I asked Francis Davey, MySociety's barrister, if it's legally possible to create an enduring or repeating FOIA obligation on a government agency, so they have to keep publishing the documents; apparently not, and there are various tricks they can use to make life difficult, like assuming that the cost of doing it again is the same as doing it the first time, totalling all the requests, and billing you for the lot.