124 characters, with the following features:

• Digits are displayed on a single line instead of scrolling the screen. (Tested only on Linux with bash.)
• Execution takes anything between $D and $D*10 seconds to run, when using base 10. Thus, if $D == 10, the program may run for as long as 100 seconds or 1 m 40 s. $D == 15 will break the "bonus barrier".