Leandro Pereira has created hardinfo, a useful user-friendly GTK+ utility to browse the hardware information on one's machine. It also includes a bunch of benchmarking tools too.
To install, simply use:
apt-get install hardinfo
and run with Applications->System Tools->System Profiler and Benchmark or run from the command line using:
The tool presents information from /proc and /sys in a very easy to user and clean GUI. The view is broken into four categories:
Computer: OS, kernel modules, filesystem, display, environment variables, users.
Devices: CPU, memory, PCI, USB, printers, battery, sensors, input, storage, DMI, resources.
Network: Interfaces, IP connections, routing tables, ARP table, DNS servers, statistics, shares.
Benchmarks: Blowfish, CryptoHash, Fibonacci, CPU N-Queens, CPU FFT, FPU Raytracing.
Below are some sample views of my machine using hardinfo:
Quite a handy tool.