I thought I'd go to each of the main party websites and look at the campaigns which they're running.
The methodology was to search the homepage, and when searchboxes were available I would use them to try and find the pages. If I've missed a campaign I will be happy to correct this situation. I've tried to be as even handed as possible and include all the major parties for Westminster.
The Lib Dems currently have three campaigns
The first is showing Tony Blair and George W. Bush in a romantic dance, with the caption 'let's dance to another tune'.
This campaign comes in two varieties, there is the large box and then there is the traditional banner.
Their next ad talks about the run up to may, and asks directly for donations to 'make it a fair fight'.
Like their other campaign this one comes in two varieties, there is the large box and then there is the traditional banner.
The third campaign is a rotating button, it's small and always links to the most prominent campaign of the moment.
Of the three campaigns, this is probably the one which seems to be the best, as it's not as intrusive and so much more likely to be used. It's not the 'most obvious', but being too obvious would reduce takeup.
I am also aware of unofficial campaigns here. These include simple icons (if you can call these a 'campaign' - I don't, I call them links!)
There is Lib Dem This Time, which is a touch more organised.
Labour has an 'action centre' (sounds like something from Captain Scarlett to me!)
They don't seem to have any online campaigns which provide easy links for websites, I even looked in the 'Make a Difference' page.
Of course, there may be something behind the Members Login.
As for unofficial campaigns, there is 'Backing Blair'. It's dubious whether this is a supporting campaign or not, given that the mandate is 'Labour In, Blair Out', but we'll have to leave that to the reader to judge.
The Conservatives website does have a series of options which present themselves, as well as a 'party toolbar' (which I'm not going to install even in the interests of research).
The Tories have quite discrete buttons and they should see a reasonable uptake as a result.
I am not aware of any unofficial campaigns which reference the Tories.
Obviously, I will not be able to keep up to date with all the unofficial campaigns out there... or even all the official ones. If there are errors and omissions, please post a factual comment on the site.