This works, but I don't know if it is what you are after:

#!/usr/bin/perl -w
use strict;

my $string = "4 I am thinking99 of a 34.56number" .
             "be110.2tween 100 an100d 1000, " .
             "and it isn't 55...";

# forgot the '+' qualifier on the split token!
my @ary = split /[^\d.]+/, $string;

for (@ary) {

# don't need this anymore
#    next if /^$/ or !/\d/;  

# because of the way we split, 
# there could be multiple ".."
        s/[.]+/\./;

# convert string to number (thanks to prev suggestion)
        $_ += 0;
        print $_, "\n";
}
[download]

It ain't pretty, but it does the trick.

UPDATE: fixed the split token to eliminate empty strings

PCS