One interesting take on calculating ROI for brands on Twitter. It doesn't evaluate the quality or type of posts, though, making the communication portion -- probably the most important part -- unaccounted for.

Thought this was very cool that a business site like Forbes would put out an office pranks site. Definitely adds accessibility to the brand.

This is a fun idea that i could see brands easily participating in. You can completely deck your car out, and two people can do it in a couple of hours. However, more applicable to brands might be a smaller icon that can be applied in about 5 minutes. Cost: $35.

If you figure that any car it goes on will be seen by thousands of people, you're looking at a potentially innovative campaign for a great CPM. (Just don't be the 500th company doing so.)

Interesting tool, Tagatum, looks for common pairings of tags in blog posts. This would be a way of gauging media (blog) coverage, based on a given keyword. As an example, I entered 'Disney', and then looked for pairs. While 'film' is a highly popular tag compared to 'hannah montana' (according to Tagatum), the 'disney - hannah montana' pair ranks above the 'disney - film pair'.

There were a number of other 'title-based' tags that also came up very high in pairing with 'disney'.

I think quick bookmarking and reminder techs like these are interesting components of marketing campaigns. Clearly they need to have a reasonable user base, but for awareness-building campaigns, giving someone what's basically a memory-aid for a campaign they just saw has obvious value.