- Indicate how to increase coverage?
- Collect data for path coverage.
- Tests.
- Documentation.
- Profiling and speedups.
- BEGIN and END blocks.
    Code in modules without subs.  Requires callbacks from perl?
- Move away from Data::Dumper.  To?
- Work with memoize.
- Fix up Devel::Cover::Op
- See if the XS code leaks, and fix it if it does.
- Specify where html output goes.
- Different criteria for different runs.
- Subroutine coverage
- Improve textual output
