They are labor intensive, someone has to watch them all the time. The business owners in Hillyard have purchased ISP addresses so their camera feeds can be viewed at the COPS shop.
SPD needs license plate numbers, times and dates. Descriptions of the people who show up frequently, but be careful while you are doing it so you don't get into a confrontation with drug dealers or other criminals.
Report incidents even if you don't think police is going to come out - it helps the police department build a pattern of activity, if there is one. Some of this information may be useful in court.
COPS suggests Business Watch - a plan like Block Watch, just for businesses. This effort has been very successful in the International District on East Sprague.
Note: These are essentially my notes, the way I take them at any meeting I cover - experimenting with live blogging.