persiting complex R objects

Is there a method to save a large and complex R object (either as a 
binary or text file) so that it can be loaded and reused at a later 
time? Specifically, I am creating large lists (several thousand 
elements), each element of which is either a vector or a matrix (with ~ 
2000 rows). The dimensions of the matrices are not all the same. My 
ideal would be a set of functions of the form

obj <- create() # computes  the object
save(obj,filename)
obj <- load(filename)

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Richard Mott       | Wellcome Trust Centre 
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