panaLiX
screenshots
A sysfail ("kernel panic") situation results in a stacktrace with C++ name demangling and provides values of passed arguments (unless their value on the stack was changed by the functions).
The sysfail message is also sent to port 0xE9 (bochs echo).
A slightly differented font loaded onto the VGA and circle drawn with a routine that computes new glyphs for a subset of the font.
Clearly text mode
Too big radius uses too many characters and hijacks the letter-chars :)