In an effort to branch out an learn my "one language per year" like a good little developer, I've decided to start tooling around with Groovy and it's most famous offspring, Grails. I spent a week on a test app just to get my feet wet with the Grails conventions for GSPs/Controllers/Domain object and such, and I must admit that it's been soooooo easy to get things up and running. And not having to recompile and bounce the web-app every time I make a change is nice - even though when I change a domain class the web-app bounces itself (controllers are better in this regard).
For a nice-sized project with Grails, I'm going to implement a basic e-commerce site as I have a little bit of experience in that domain :). I'm planning on attacking it in a TDD manner, and applying lots of YAGNI (wow, I really need to master that skill!). I'm also going to integrate with Google Checkout for doing purchases - all test/beta/sandbox, nothing for real. I've done integrations with credit card processors, loyalty point programs, and PayPal, so I figured I'd checkout Google's API and see what I find.
I'm also curious to see how grails can deal with HTTP header things like ETags and If-Modified and such. I'm not totally sure if that's the domain of the web-app or web server, but I'm itching to find out - as I'm on a limited bandwidth host, and I need to conserve by bandwidth bytes!
More reports as I progress.