Since your numbers are the initial field, and are terminated by non-numbers, you can just treat the whole string as a number and Perl will Do The Right Thing: 
print sort {$a <=> $b} <DATA>;
__DATA__
30|microsoft
70|aol
76|netscape
5|trouble?
35|mozilla
40|opera

[download]
No need for splitting or Schwartzian Transforms.
Caution: Contents may have been coded under pressure.

In reply to Re: How can I sort this data on the first field by Roy Johnson
in thread How can I sort this data on the first field by Anonymous Monk

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