Of all the "tricks" Vista has available, there is one I use the most frequently and appreciate more than any other. That is resizing text.
I originally found this trick on Techlog.
I do not have perfect eyesight. I can focus on far away things or close things, but my eyes strain more than usual when making the transition. This makes my eyes very tired by the end of the day. So when I am still crunching through Email at 8pm, it doesn't matter how much coffee I drink, my eyes still hurt when staring at small text on my high resolution laptop.
Here's the fix, hold down the ctrl key and either role your mouse wheel up, or slide your finger up along the slider on your touchpad. Mine is on the right side and is indicated by a series of lines. This makes the text within the window larger. Now scroll down to make it smaller.
This trick works in an Email message, on web pages in IE, pretty much any readable text you can click on it and then make it bigger without actually changing your dpi setting or resolution. It also works on icons in Windows Explorer, or on your desktop. You can't resize text you are editing because then you would have no idea what it is going to look like when someone else opens it.