See: http://news.bbc.co.uk/1/hi/technology/7041183.stm

The switch has been thrown on a telescope specifically designed to seek out alien life.

 Funded by Microsoft co-founder Paul Allen the finished array will have 350 6m antennas and will be one of the world's largest.
The Allen Telescope Array (ATA) will be able to sweep more than one million star systems for radio signals generated by intelligent beings.


The ATA is being run by the SETI Institute and the Radio Astronomy Laboratory from the University of California, Berkeley.
It looks like a 21st century update of the SETI project.

I would think that the most likely 'first contact' with another intelligence would most likely come from a project such as this one. Either picking up electromagnetic signals they're using or even a 'beacon' that is intentionally transmitting to signal that intelligent life is present.

I don't know what the chances of contact are estimated at but I presume the odds are very low.