A snapshot database is NOT <= Original.  It will be = Original minus the log.

See proof below.  Commands in black, results in red.

exec sp_helpdb UPSRC   -- show size of original database (approx 301 GB)

 name            db_size       owner               

 --------------- ------------- --------------------

 UPSRC           301718.13 MB  RAINBIRD\PSAdmin    

 name            fileid filename                       size        

 --------------- ------ -----------------------------  -------------

 rbprod_data     1      F:\mssql\data\UPSRC_Data.mdf   253744832 KB

 rbprod_log      2      F:\mssql\data\UPSRC_Log.ldf    55214528 KB 

CREATE DATABASE UPSRC_Snap

ON (NAME = rbprod_data, FILENAME = 'f:\mssql\data\upsrc_snap.ss') AS SNAPSHOT OF UPSRC

exec sp_helpdb UPSRC_Snap  -- show size of snapshot database (approx 301GB)

 name           db_size      

 -------------  --------------

 UPSRC_Snap     301718.13 MB 

 name            fileid filename                       size         

 --------------- ------ ------------------------------ --------------

 rbprod_data     1      F:\mssql\data\UPSRC_Data.mdf   253744832 KB 

 rbprod_log      2      F:\mssql\data\UPSRC_Log.ldf    55214528 KB  

dir f:\mssql\data   (show size of database files on disk)

 11/27/2006  07:13 PM   259,834,707,968 UPSRC_Data.mdf

 11/27/2006  07:13 PM    56,539,676,672 UPSRC_Log.ldf

 12/11/2006  04:12 PM   259,834,707,968 upsrc_snap.ss