Most laptop power supplies are made to handle anything from 100 to 250 volts at anywhere from 50 to 60 Hz. Less expensive power supplies (like those little "wall warts" that come with most electronics) are often not capable of dealing with the power. If they're not "smart" enough, they'll overpower your devices.
For example, my laptop's power supply is stamped as a 100-250 V, 50-60 Hz power supply. I would have no qualms about running my laptop off non-US grid power (it runs fine in Japan, regardless of which system you're on -- Japan has two different electrical grids, one basically just on Kyushu, and the other everywhere else). My cell phone's little power supply, on the other hand, is labeled as 120V, 60Hz. It is not as likely to be well-served by connecting to a 127 V, 50 Hz grid.
I'd guess that the faster chargers (the new 1-hour, 30-minute, 15-minute, and thermonuclear AA chargers) are more likely to have beefier, more adaptable power supplies (given their current loads) than more basic chargers, but you can usually tell just by looking at the stickers or stampings on the power supply's case. (If it gives a range, it's usually better built, and you can see if you're in the range.) Electronic devices with compliant power supplies should show no change in function (since the electricity is all converted to DC anyway), but electric devices (such as a hair dryer with plain old motors and coils) will operate differently.
Of course, as the linked page says, it is generally a wise idea to have some sort of surge suppressor between your stuff and the wall, but if you've got multiple chargers, laptops, and all, it might be a good idea even if there were perfect power.
