See second to last input please.
Note: I was using http://try.mongodb.org/
> person = {fullname : "Derek Litz"}
{
     "fullname" : "Derek Litz"
     }
> db.people.save(person)
"ok"
> db.people.find()
    [ 
      {   "_id" : {   "$oid" : "4df3b39ccc93747e68039f08"   },   "fullname" : "Derek Litz"   }
    ]
> db.people.find({fullname : 'Derek Litz'})
    [ 
      {   "_id" : {   "$oid" : "4df3b39ccc93747e68039f08"   },   "fullname" : "Derek Litz"   }
    ]
> db.people.find({fullname : /^D.*/})
    [ 
      
    ]
> db.people.find({fullname : {$regex : '^D.*'}})
    [ 
      {   "_id" : {   "$oid" : "4df3b39ccc93747e68039f08"   },   "fullname" : "Derek Litz"   }
    ]
>