VisualMon is a concise dashboard for Java web applications, it shows statistics gathered by JAMon, reduced to the data relevant to the concrete web application and with a visually pleasant appearance.
Rapidlogix is an open source application performance management tool optimized for distributed production environments. It allows to increase time-to-market of performance improvements and prevent performance regression
Free Java monitoring library to easily instrument apps to measure performance detail over time with minimal overhead. Has dashboard, SVG graphs. Extends Jamon and its statistical data, same usage. http://www.e-peas.com/opensla/. JMX, SNMP planned.