Well, I suppose it depends on how you value *your* time. :-)

Last week I needed to concatenate some 50 PDF files that comprised
a logical document so that it'd be easier to search one document.

Because I didn't want to bootup a Windows box to use Adobe Acrobat,
I used the free PDF Split and Merge program that's written in Java
and available here:

<http://http://www.pdfsam.org/>

There's a bug in the program such that it doesn't automatically add
".pdf" to the output file and it was stuck in a loop eating all CPU
time. On a dual-core system it was trivial and fast to kill the
process. I tried it again on a single-core system and it took about
5 minutes to bring up a terminal window, identify the process and
kill it (all using top) -- the errant program had literally taken
over the system (and a ^C or clicking the window's "Close" did nada).

The cost of computing has come down but people time is expensive.
The last two systems I bought new were both dual-core and both under
$300; one is a Pentium E2180 2GHz Core-Duo (from Fry's Electronics)
and the other is an AMD Athlon 64 X2 Dual Core Processor at 2.2 GHz
(from Office Depot). Both dual-cores, BTW, are 32-/64-bit capable.