How can I print a very small snumber, like 9^-10 or something?

What number is that supposed to be?

At the moment I'm just getting output like '3e-009', which is not very usefull

That is http://en.wikipedia.org/wiki/Scientific_notation#E_notation, its useful it means 3 times ten to the power of negative nine

$ perl -le " my $num = 3e-009; $num =~ s{[eE]([+-])?0+}{ * 10**$1}; pr
+int $num; "
3 * 10**-9

$ perl -le " print 3 * 10**-9 "
3e-009
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