Google Charts - Interactive charts for browsers and mobile devices.

WordItOut - WordItOut is the word cloud generator that gives you control with many custom settings.

Highcharts - A charting library written in pure JavaScript, offering an easy way of adding interactive charts to your web site or web application

Wordsalad - Wordsalad is an app for generating “word clouds” from text that you provide.

ZoomCharts - Creating meaningful and aesthetically pleasing data visualizations and incorporating them into your projects is easy with the tools offered by ZoomCharts.

TagCrowd - Create your own tag cloud from any text to visualize word frequency.