Disclaimer: I've solved the problem using Expressions from System.Linq.Expressions, but I'm still looking for a better/easier way.

Consider the following situation :

var query = 
    from c in db.Customers
    where (c.ContactFirstName.Contains("BlackListed") || 
           c.ContactLastName.Contains("BlackListed")  ||
           c.Address.Contains("BlackListed"))
    select c;

The columns/attributes that need to be checked against the blacklisted term are only available to me at runtime. How do I generate this dynamic where clause?

An additional complication is that the Queryable collection (db.Customers above) is typed to a Queryable of the base class of 'Customer' (say 'Person'), and therefore writing c.Address as above is not an option.