Having a good font management system in place is invaluable, both for tracking and managing fonts and to fight Font Fatigue. I have actually worked for companies in the past, that had no font management system in place at all. I used to keep the fonts in folders, but never de-installed. Looking back on that, I cannot imagine work without a font manager anymore!
I have tried out all the main font management tools, including Suitcase and Font Agent Pro, but even the most expensive seemed basic at best. Then I tried out MainType from High-Logic and I was in font heaven! The main screen is customizable, so you can adjust it to what you need to see for each font. One window shows you all the installed fonts, seperately from the fonts that you can group- either per project or per client. You can search fonts depending on the characteristics, and it even exports groups of fonts to HTML for easy viewing. In the same window, you can view typographic data per typehouse, the font character set and a sample text. You can also easily organize the fonts per typehouse or per type (serif/ sans serif/ handwritten) within a group as well. It also identifies broken font files for you.
For the best font workflow, try out MainType! You can purchase it from High-Logic or try out the demo version.