Segmentation based on variable equivalency without discreetly identified values

[#1]

I NEED to be able to build segments that don't require discreetly defined variable values, but can be based on var1=var2.

Any easy example would be this:

[Visit bucket [entry pagename]=[exit pagename] AND [path length] >1

Another, more difficult example:

Show me all eVar1 values that have both mobile phone and tablet instances.

[#2]

This is a very similar idea to: http://ideas.omniture.com/t5/Idea-Exchange-for-Adobe/The-ability-to-segment-by-unique-valu es-in-a-variable/idc-p/11710#M6490

Clearly there is demand.