UptimeMac

Graphical uptime display (displays the machine's current uptime in a window on the screen using a mock-LCD appearance), and offers crash-proof logging of uptime to disc (commits it to disc once each minute).

Permits copying of the machine's uptime to the clipboard, and lets you read off uptime via AppleScript.
What's new in this version:
The uptime display is no longer limited to 28-31 days; it will now continue correctly to 999 days (in theory anyhow), at which point it will return to zero. A workaround is in place for the issue wherein the display ceases to update each second after, it seems (I have yet to reboot!), just over 24 days; the program is now patched to draw in an updated uptime readout each time the LCD window is activated, so each time you switch to the program you will get a new reading....