Oh, and before I go, let me heartily recommend the hostel I stayed at
for my eight days in Paris, the Foyer International Des
Etudiantes near the Metro/RER Luxembourg stop. At least during the
summer the Foyer is open to everyone for minimum stays of 5
nights. Prices this summer (including a continental breakfast) was
 
 160 FF per night for a single room
 110 FF per night and per person in a twin-bedded room
 
Kitchens on floors. Dorm-sized fridge and sink in room. Toilets and
Showers in the halls. Bring your own towels. No curfew and no
lockout. Foyer is open all night for you to come and go. Also, make
sure to visit the terrace on the top floor - nice views of the Paris
landscape.  The Foyer was clean, and rooms were airy.
 
This foyer is in a great location - near the Sorbonne and the Pantheon
in the Latin Quarter and smack dab between the Fifth and Sixth
Arrondissements. A minute walk from the beautiful Luxembourg Gardens
and a 5-10 minute walk from the Seine. The area was a bit touristy
when I was there.  For example, beware the Greek restaurants off of
St. Michel. The one I visited had sub-par food compared to the rest of
my dining experiences in Paris.
 
Write to foyer with dates you want to stay and what type of room, and
they will write back if they have room. Otherwise visit it while you
are Paris early in the morning to see if anything available, or if you
can reserve for the next day on.
 
93 boulevard Saint-Michel.
75005 Paris
Tel: 43.54.49.63