So it seems like the General Election has been a Good Thing for the news media’s interactive developer teams… Here’s a quick round up of some of the interactives I’ve found…
First up, the BBC’s interactive election seat calculator:
This lets you set the percentage vote polled by each party and it will try to predict the outcome…
The Guardian swingometer lets you play with swing from any two of the three big parties to the third:
The Daily Telegraph swingometer lets you look at swing between any two parties…
The Economist also lets you explore pairwise swings…
The Times doesn’t really let you do much at all… and I wonder – is Ladbrokes in there as product placement?!
Sky doesn’t go in for modeling or prediction, it’s more of just a constituency browser…
The Sun probably has Tiffany, 23…
From elsewhere, this swingometer from the Charts & numbers – UK Election 2010 blog lets you model swings between the various parties…
As to what swing is? It’s defined in this Parliamentary briefing doc [PDF]/
OUseful.Info, the blog... 
Do you live in one of the top 100 constituencies where you could prevent a Tory majority?
http://bit.ly/bDizHY
There’s a 2D/3D swingometer here too by Paul Crowley of LShift – useful for exploring the landscape of possible seat allocations given different national poll ratings. (Assuming, of course, a uniform national swing.)
http://dev.lshift.net/paul/election/swingometer/