After starting to use Picasa more, I find 'Straighten' in 'Basic Fixes' in Picasa very handy. It is not obvious to me at first.
When I examine many of my pictures closely, I notice that I have many that are not aligned horizontally when I position the camera vertically.
And I find the 'Focal b&w' in 'Effects' quite useful in that it creates a very different picture from the original
Walking through Carneval
2 hours ago