VMware Labs released a new Fling called VisualEsxtop. The download is available as ZIP package and is about 5MB.

Quote taken from the Fling page:

VisualEsxtop is an enhanced version of resxtop and esxtop. VisualEsxtop can connect to VMware vCenter Server or ESX hosts, and display ESX server stats with a better user interface and more advanced features.

Features

• Live connection to ESX host or vCenter Server
• Flexible way of batch output
• Load batch output and replay them
• Multiple windows to display different data at the same time
• Line chart for selected performance counters
• Flexible counter selection and filtering
• Embedded tooltip for counter description
• Color coding for important counters

Requirements

You must have ESX 3.5 or above. Works with vCenter Server 4.0, 4.1, 5.0 and 5.1.

Installation

1. Download visualEsxtop.zip and unzip the file.
2. Make sure Java 1.6 or beyond is in the PATH.
3. Type export JAVA_OPTS=-Xmx2048m if loading large amounts of data
4. Run visualEsxtop.sh (linux) or visualEsxtop.bat (Windows)