Not really.
You can use ClassVariables though. Here's an example for Sets:
Object subclass: #MyClass
instanceVariableNames: ''
classVariableNames: 'MyClassVar'
package: 'MyPackage'
MyClass class>>initialize
�� �� super initialize.
�� ����MyClassVar := Set new.
MyClass>>foo
�� �� self bar:��MyClassVar
Obviously sets are not as easy to deal with. You cannot mutate empty arrays/bytearrays, if you concatenate something it creates a new object. You can add things in sets. So you need to be careful... You can make the object read-only to avoid issues (MyClassVar beReadOnlyObject).