Google Reader breaks a cardinal rule of presenting lists. Manual sorting is great, but by default use (or at least support) the most natural dynamic sorting of the information.

As you play it, the map pans and zooms to follow the action, it shows troop movements and major offensives, and it redraws the front line with each major battle. Why does all this come across so well? Because the creators of this tool made good trade-offs given that their medium was the web.

Even if 99 of these 100 ideas are not right for your product, that means one of them is and you have an immediate action you can take to boost sales in 2009.

Users are usually pretty understanding of errors if you let them know exactly what happened, why it happened, and what they should do about it.