Well, I had no new ideas (except for a few which require CSS knowledge) so I have no new hacks of my own as of now. However, this post points to some good hacks/add-ons/template mods that I have seen in the neighborhood recently:
1. Hacked Son of Moto template by Deniz of imessengr.
2. Adsense beside your posts in blogger beta by Deniz of imessengr.
3. Adsense between the posts (adding adsense directly to the beta template) by Loui$$ of Blogging No Secret.
4. Template theme switcher (and tutorial to host Blogger Beta CSS externally) and hacked Blogger templates with this functionality (inbuilt) by PurpleMoggy.
In addition, I have found my interaction with Deniz and posts from "Blogging Secret" very informative with reference to Adsense related tips (especially for Blogger Beta).
BTW this post is done directly from a nice but nifty Firefox extension called Performancing. I really like their idea/design and concept, especially because I am yet to see my first post from Google Docs appear on my test blog.