There are the high costs associated with calling sources scattered across the country; the occasional missed call that was crucial to completing a story on deadline; or even the harried scramble for a tape recorder, fresh batteries and connectors required to record an interview.

Google’s latest project, Google Voice, helps the journalist with all of these pitfalls, and more.

(Invitations are going out to pre-registered users on a first-come, first-served basis, so sign up for a invitation request.)

What are some things Google Voice can do for you?

One Number for Life

All incoming calls and text messages received by your lifetime Google Voice number can easily be routed to any phone device you choose.

If you are near your desk phone during the day, Google Voice can send all calls there during the hours you specify. Google Voice also handles each caller individually, so if you want to receive your editor’s calls immediately, but send grandma straight to voice mail, no problem.

Google Voice, however, is much more than call routing. When you receive a call you have the option to take the call immediately, send the call directly to voice mail or even listen in to your voice mail as the caller is leaving a message. If you are already on a call and another call comes in, Google Voice can conference the caller in.

Speaking of voice mail, Google Voice provides free transcription services, so that you have the choice to read your voice mail via e-mail or SMS. If text isn’t your thing, you can also download your voice mail as an .mp3 file or embed it into a blog post.

Google Voice Mail Transcripts

Call Recording

Update: This feature is only available for calls received by a Google Voice number.

Whenever you are on a Google Voice call, hitting the “4″ key on your telephone turns recording on or off. Some states require consent to record from other parties on a call so be sure to check the laws in your state. Google Voice also plays a audible message to all parties whenever recording is turned on or off.

Call record can be very handy for interviews conducted in a pinch. No need to lug around an extra device or special adapters. And, once your conversation is in Google Voice, you can download the .mp3 for further editing, or embed it “as-is” in a blog post.

I tested the service with an hour-long recording and did not run into any issues other than those associated with the sensitivity of the phone mic I was using.

As always, it’s up to you, the journalist, to adequately communicate with your source regarding confidentiality and privacy. If there is any question in your mind regarding the legal requirements for taping phone conversations, please reference guidelines provided for all states at http://www.rcfp.org/taping/states.html

Google Call Record

Free, Ubiquitous Access

Finally, through Google’s relationship with telecom company Level 3 Communications, calls made within the U.S. using the Google Voice application are free, and as always, a detailed history of everything that you do in Google Voice can be accessed through your internet browser. International calls place through Google Voice, however, are not free, but Google does provide extremely competitive per minutes rates.

Google is also working on versions for popular mobile phone OS’s, like Google’s Android, Apple’s iPhone, and RIM’s Blackberry, which will make taking advantage of Google Voice’s lower calling rates and call handling features that much easier.

Google Voice is just the latest in a long list of guru-grade applications the company has released over the last few years. Google’s growing “suite” of applications” in the cloud”, like GMail, GChat, Google Reader and Google Docs, is quickly becoming the baseline dashboard for the prolific mobile reporter and a practical Swiss Army knife for online productivity.

And, from what we hear, there are more innovations to come. Google will soon launch Google Wave, set to combine the power of e-mail, chat, wiki pages and web publishing all into one simple interface.

View a full rundown of Google Voice’s features.