This script is a filter trying to imitate the effect of Clarity slider. This is in essence USM (Unsharp Mask) masked to be effective only in midtones. For best results try large radius values (100 or above).
Adds a new menu item
Select→Layer to selection
which creates a selection that exactly matches the boundaries of the current layer.
2012-08-08: Added the fixes by Aralox thanks :-)
See also http://flashingtwelve.brickfilms.com/GIMP/Scripts/layer-select.scm by saulgoode.
Creates a frame/border outside the image; the frame mirrors the original image.
The menu item appears in
Adds a menu option
Layer→Scale and move layer to canvas
which scales the layer to canvas size, and moves it so it exactly covers the canvas.
Newest version always at https://github.com/unhammer/gimp-fu