i use mine in a similar sense to fairygodmother. most often i use them to give me insight into my own behaviors and thoughts.
usually i pull two cards. i might ask what aspect of myself (or another) is in play and benefiting a particular situation. then i usually pull a second card and ask what aspect is hindering the situation (for this card i read the shadow aspect).
i've found them to work really well in analyzing the dynamics of a relationship. for this, i usually make up spreads on the spot, with such things, as what does the relationship need, what is hindering it, how does so and so see me... etc...
comparing the archtypes pulled of two or more people, often tells alot. some would appear to be more compatable than others. sometimes, the roles we play are pointed out.