Back 'in the day', if you wanted to really know what's going on out there, you'd scan the horizon for weather changes, listen to the weather radio, head to your local break for a peek, or here in the Pacific NW, bite the bullet and drive 3-5 hours to the coast and hope for the best. Sometime in the mid 1990's, thanks to the internet, webcams began to give us a window into local or even international locations without leaving your comfy chair at home. Since the cams don't cover all spots or angles, you still have to do your homework for many spots.
I use webcams to confirm if all the surf forecasts sites are correct, what the tide and wind levels are doing, and for fun, poking around to see what's breaking in Hawaii, Socal, etc. Some webcams allow you to change the angle, and one, Race Rocks near Victoria BC allows you to do that and have live audio, pretty cool. http://www.racerocks.com/racerock/video1.htm
Here's a few webcams I use often...
Living in the Ballard neighborhood of Seattle, I regularly paddle to the West Point Lighthouse, part of Discovery Park. This cam is run by a guy living south of the point. It has to be refreshed manually. Imagine the entire left side of the screen completely dry from extreme low tides in summer. I can also watch freighter and wind waves break off the point or spot a friend padding out there.
I use the following NOAA link to check weather for that location. NOAA has a tower at West Point.
Statewide Road and Mountain Cams for WA State, courtesy of the WSDOT:
Olympic Peninsula, WA State:
This site includes cams for La Push (fun winter surf watching); Port Angeles, Port Townsend, the Sol Duc River, Victoria, and Hurricane Ridge, http://www.forkswa.com/visiting-forks/webcamsontheolympicpeninsula
SurfWa, this is a good one for surf reports, buoy readings and cams,
Big Wave Dave, located in British Columbia, has several marine BC cams which are fun if you're looking for local wind and wave conditions. They cover the inside, and southern sides of Van Island, aDeep Cove in North Vancouver (Mainland), and Hawaii. http://www.bigwavedave.ca/webcams.php