Without your AC charger/adapter, you may feel like your laptop is next to worthless. After all, not only do you not have a way to charge the battery in your laptop, you don't even have a way to run your computer via a wall outlet. While new technologies are being developed every day in the area of mobile power solutions and laptop power supplies, there aren't many current alternatives to charging your laptop battery without a charger. If your problem is that you are without your original charger (which is what normally comes with a new laptop), there are some workarounds you can try that will keep your laptop humming. Keep in mind, though, that they cost money and require an advance purchase, in which case it may be just as economical and convenient to buy a new charger from your laptop's manufacturer.
Use a universal power adapter. This is perhaps the most obvious solution to your battery woes. Readily found at most retail outlets that carry electronics, a universal power adapter can range anywhere in price from $30 to $100 or more. The adapter comes with multiple tips, one of which will likely fit your laptop's charging port. When plugged in, the adapter will not only power your laptop, but will charge its battery as well.
Use a universal auto/air adapter. If you're the road-warrior type who spends more time in your car than at a desk, this might be the sensible solution for you. An auto adapter is similar to a regular power adapter, except it has a modified end that plugs into your car's cigarette lighter. The adapter will keep you powered while in your car (or inflight if it's a combination adapter), and will simultaneously charge your laptop so you're ready for those occasions when you do have to leave your car or plane for the real world.
Buy an external laptop battery charger. These are standalone devices that do not plug into your laptop. Rather, you take the battery out of your laptop, attach it to the charger, plug the charger into an electrical outlet and re-juice your battery that way. When the battery is fully charged, you reinsert it into your laptop. External chargers are usually brand and model specific, so make sure you get one that matches your laptop's specs. One advantage to an external battery charger is that you can charge spare batteries without tying up your laptop.