storing large data.frame's

I am new on R, so I have a maybe naive question:

if I have many large data.frames and I use only one or two per session, 
what's the best way?
If all are stored in the actual .Rdata, the system gets slow.
On the other hand, I wouldn't like to make a separate package for the 
data.

Take a look at the package "g.data" at your local CRAN:

g.data: Delayed-Data Packages 

     Create and maintain delayed-data packages (DDP's). Data
     stored in a DDP are available on demand, but do not take up
     memory until requested. You attach a DDP with
     g.data.attach(), then read from it and assign to it in a manner
     similar to S-Plus, except that you must run g.data.save() to
     actually commit to disk. 
     Version:
                    1.2
     Date:
                    2001-11-30
     Author:
                    David Brahm <brahm at alum.mit.edu>

--------------------------------------------------------------
http://www.reed.edu/~jones    Albyn Jones	  jones at reed.edu
Reed College, Portland OR 97202             (503)-771-1112 x7418

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