In addition to the above tools (I have nearly all of them, except for the Firefox plug-in) and you are running Windows.
1. Right Click on the image - properties - advanced ---- Contains quite a lot of exif information but it is highly dependant on your editing software.
2. Microsoft's free plug-in for explorer (and stand alone) Photoinfo tool.
Microsoft Pro Photo: Microsoft Pro Photo Tools
3. Kiwi.software.net's EXIF editor - one image at a time found here
:: kiwi's digital experiment :: works nice but is manually intensive - if you are using the old version I am.
The Elitist - formerly known as PDL