htop is an interactive process viewer for Linux. It aims to be a 'better top'
You can scroll the process list vertically and horizontally, and select a 
process to be killed with the arrow keys instead of by typing its process 
id. 

This release adds per-process I/O statistics, Unicode support, and new 
handling of CPU count for threaded processes: it can now show either 
per-thread stats or a sum of all threads depending whether user threads 
are shown or hidden. There were also improvements in mouse support.