Good-looking charts shouldn't be difficult.
Easy pie chart is a jQuery plugin that uses the canvas element to render simple pie charts for single values.
Animated Gauge Charts
Adds animated liquid charts.
Small Inline Charts
Adds tiny charts called sparklines.
Chartist - Simple Responsive Charts
You may think that this is just yet an other charting library. But Chartist.js is the product of a community that was disappointed about the abilities provided by other charting libraries. Of course there are hundreds of other great charting libraries but after using them there were always tweaks you would have wished for that were not included.