I need to find it but there is an attribute that allows you to 'hide' a property/method etc from intellisense. I jsut can't remember the name of it off the top of my head. Beyond that I don't know of anything that changes intellisense.
Edit:
System.ComponentModel.EditorBrowsableAttribute
Design-time attribute.
Specifies whether IntelliSense support should provided in the property editor for a property. This attribute can also be applied to methods and events. The argument of the constructor of this attribute is a value of the System.ComponentModel.EditorBrowsableState enumeration. The default value, System.ComponentModel.EditorBrowsableState.Always, is implied when this attribute is not applied. Apply this attribute if you want to hide a member in IntelliSense.
The enum has several levels including 'hide advanced members' etc.
John