If you work extensively with layers in Photoshop, you may be suffering from layer-palette-thumnail-squintitis, a condition resulting from squinting at the tiny little thumbnails in the layer palette. Until medical treatments are available, you can just make them bigger using the steps in this short but sweet recipe.
To change your layer palette from small thumbnails to larger ones like this:
Click on the little pull down menu (a small down arrow and three horizontal lines in CS3 as pointed to in the image below) and select the Palette Options… choice:
The resulting window (shown below) has selections for three sizes of thumbnails. The default size is the top (smallest). Select the size you want and click OK to save the setting.