<Grin> Yeah, many of the key perl functions return different data depending on context. Localtime(), for example, returns an array of time stats unless used in scalar context, in which case it returns a nicely formated time stamp for human consumption.
I also like the convenient perlisms like:

print LOGFILE "\$input = $input" if DEBUGING;

# Instead of:
if( DEBUGING )
{
    print LOGFILE '$input = ', $input
}
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