I've blogged previously about using ldp, a handy tool:
I had to use it again recently to look up the DLs a user was on, but the default display in LDP does not contain enough characters for that attribute to show the full results for any real-world case (I myself am on... let's just say way too many DLs).
So in order to get the full list, I had to use ldifde (which should be on any win2k3 box by default). The syntax is as follows:
ldifde -d "DNOfTheObject" -f c:\export.txt
So for example:
ldifde -d "CN=Exchange Goddess,DC=corp,DC=mycompany,DC=com" -f c:\export.txt
Then look in export.txt for MemberOf.
Of course, this can be used to look up any attribute... I just find it handiest for MemberOf and use ldp for most everything else.