When I save a screenshot I want to be able to specify any name I want (and maybe destination directory). Sharpshooter for mac does this, but it's a ridiculous $15. Cheaper alternatives?
Changing the prefix part of the names
Changing the format of the names
To something like
(The default format is currently something like
Changing the default location
Using custom scripts
I've disabled the default shortcuts and have assigned shortcuts to scripts like
A much easier way than Laurie's answer is to use a free application called Deeper. It is really easy to use. Just enter in the name of that you want in the screenshot name field (under the General tab):
Click "Apply" and you are done. A nice feature of Deeper is the ability to restore all the default settings. If you've made a change to the settings that is causing your system to act up, no problem! At the bottom of each tab is a button that says "Restore Defaults". Deeper will fix up all your settings. I highly recommend this app, as it is free and adds a great deal of customization that OS X doesn't provide.
Skitch lets you do this, as well as online sharing, annotation, and drawing, and it's free.