A cordless battery powered circular saw is one tool that I will always keep in my possession. When they first came out a lot of experts were skeptical about how much power they would have. Well they aren't as powerful as a corded circular saw but they run a close second.
 
Cordless battery powered circular saws are designed to handle 2x stock. All the saws come with carbide tipped blades. This is because you need a sharper, better cutting blade with this tool because you wouldn't have the reserve power to force the blade through your cut if the blade was dull.

Most manufacturers sell these saws in kits with other cordless battery powered tools, usally a cordless battery power drill. Skill is one manufacturer who does not sell this tool by itself. So check around and see if anybody does sell it by itself and also check if it comes with a extra battery. I recommend getting a extra battery so that while you are working you can have a battery ready for when the battery in the saw starts to lose power. Most of these batteries recharge themselves in about a half hour.

Safety is not a big concern because this tool is lightweight and easy to handle. Just be careful to always remember that when the battery is in it's just like having a corded tool plugged in.

On a scale of 1 to 10 on the importance of having this tool in your shop, I give it a 10. This tool is great for many projects and so easy to handle it is a must have tool for everybody.