I went through the same question myself a few weeks ago.
I was first searching in "Online Reporting" solutions, then I realized that maybe Google Analytics could cover most of the data I wanted to display in my dashboard if I used events correctly.
Unfortunately Google Analytics doesn't allow you to have a custom dashboard. So I started looking at third party solutions that use Google Analytics.
Could find anything that suited me enough and I developed my own dashboard that shows Sales (with diff from last week), New Users (with diffs) and a few more KPIs. (It also shows stats on the trending searches on my website).
Anyway, I allow anyone who is working on a elegant solution for startup dashboards to contact me, I will gladly answer any questions and serve as a guinea pig.
Cheers.