I have an ADSL modem, wireless router, and two PCs plugged in that I keep running 24/7.

I had noticed problems with the modem/router hanging occasionally, today I left my son's guitar amp plugged in and it led me to the fact that the devices are suffering power surges as the amp made a crackling noise just when the router hung up.

The PCs have never (or maybe once) gone off, but the router and lights have been affected by voltage fluctuations, just wondering what my options are to keep it more stable. (I like to know I will be able to dial in after being away for 2-3 weeks.) I'm not 100% sure on the wattage my devices are pulling, but would a cheap UPS run that?

Or do I just get a surge protector?