Option 2:
iCall
iCall is another tool you can use to make free
internet phone calls. With iCall, you can make free
calls from PC to phone using their free software.
You can make calls from anywhere in the world with
your computer, but for the FREE call, the number you
call must be in the United States or Canada. You
can't make free phone calls using iCall if you're
calling outside the US or Canada. iCall is available as a free desktop application
for Windows, Mac OS X, or Linux and as a free iPhone
app. Free phone calls will be disconnected after a
short five minutes but you can call the number back
again as many times as you want. You will also hear
an advertisement before each call that's around ten
seconds long.
A flash-based version of iCall is also available
on their website but free calls here are limited to
three minutes.