It is not uncommon for intermediate-level commercial switches (not low-end consumer switches...) to be marketed as "managed switches". These switches are accessible by IP address so that they can be configured ("managed") remotely.
In addition, there are what are known as "Layer 3 switches" which integrate a router into a switch. The purpose of these intermediate-level devices is to facilitate VLAN trunking all within the same device ("router-on-a-stick" is a common configuration...).
So not all switches/bridges exist solely at Layer 2, but for practical reasons, it is safe to think of switches as only Layer 2 devices.
And for what it may be worth, Henning is not a fan of Layer 3 switches.
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