Bugs:
     Negative delta in idle CPU time is not supported

List of plugins to implement:

     MPD
     Alarm clock
     portage
     SMART monitoring
     System tray
     Eyes
     Applets
     Taskbar
     Application menu
     UPS
     Blueshift integration
     Backlight control
     Thermal monitoring (`sensors`)
     SSID
     Keyboard layout
     EWMH
     Meteor showers
     Lunar and solar eclipses
     e-mail
     Identify active and visible windows
     natural disaster reports
     /proc/interrupts
     /proc/net/sockstat
     /proc/net/sockstat6
     /proc/net/wireless
     /proc/net/arp
     /proc/net/rarp (requires RARP to be configured into the kernel)
     /proc/net/igmp
     /proc/net/raw
     /proc/net/tcp
     /proc/net/udp
     /proc/net/unix
     /proc/sysvipc
     /sys/class/rtc
     /sys/class/rfkill
     /sys/class/leds
     /sys/class/ieee80211
     /sys/class/bluetooth
     /proc/buddyinfo
     /proc/zoneinfo
     /proc/pagetypeinfo
     /proc/[pid]/

Demo plugins:

     linereader
     solar
     weather
     hdparm
     ii
     powersupply
     lid

Terminal mode

workspace and layout switching in xmonad
fix so that ropty works with wall too
use C to gather system information efficiently, which
    will also circumvent the global interpretor lock