Handheld radio for emergency use...

All,

I have an ICOM A5 that I use for getting ATIS, clearances, calling for
fuel, etc. If I were to go down in a remote off-airport, middle of
nowhere situation (not at all unlikely here in AZ or NM) am I fooling
myself to think I could raise someone on 121.5 or the local center
frequency?

Obviously, I am not going to be able to talk directly to a controller,
but I am thinking I should at least be able to reach overflying
aircraft... Do airliners or other aircraft routinely monitor 121.5? I
do hear some carriers on the freq from time to time after a missed
handoff or something. Would the handheld even have enough power to
reach other aircraft? I am assuming so...

I'd really love one of those 400Mhz emergency ELTs w/GPS, but they're a
bit pricey...

--Dan