I've been playing around with Popfly for a while now, so I thought I'll post something about it.
Popfly is one of Microsoft 'newest' online toys that allows you to create mashups and blocks. Mashups are pieces of code which using Silverlight will display something nice to show in your web site, Facebook profile, Live Space, etc.
You can build your block from the online editor (not too nice) or you can download the VS2008 Popfly Explorer and build your blocks from VS2008, where you can debug your code.
I created a few mashups and two blocks. One of them is called Picasa Web Block and takes two parameters, username and albumname. After filling those up you'll get a collection with all the pictures from that album and you can display those pics with any of the display blocks available.
The other block was a little trickier, it takes a US zip code or a location code and the temperature unit (c or f) and it'll return the "current" weather conditions from the given location. The weather forecast is provided by Yahoo! Weather which takes the data from Weather.com.
In my spanish blog (scroll down all the way) I have a mashup I created with my Yahoo Weather block and the Live Earth block from Microsoft. Here's a picture of what it looks like.
Mahalo to my visitor from Hawaii :)