Raven's System Stats allows users to collect detailed information about an operating system, including kernel architecture, distro, operating system, kernel version, glibc version, name of login shell, number of CPUs, CPU description, hyperthreading support, CPU MHz, CPU cache, bogomips, used and total RAM, used and total swap, filesystem size and type, uptime, unique users logged in, total login shells, currently running processes, total processes since bootup, load average, X resolution, and the number of X servers running.
YASIS is a very detailed sysinfo script that displays individual stats or grouped info. It only requires lspci and common tools found in any distribution. Check the page for example outputs. It displays distribution/kernel, CPU count/cache/load, disk/swap/RAM used/free, network info/speed, CPU temp/fan speeds, X environment info (wm/de and display info), bandwidth speeds, and more.