<p>As the local subversion czar i explain to everyone to keep only source code and non-huge text files in the repository, not huge binary data files.  Smaller binary files that are parts of tests, maybe.    </p>

<p>Unfortunately i work with <em>humans</em>!  Someone is likely to someday accidentally commit a 800MB binary hulk. This slows down repository operations.  </p>

<p>Last time i checked, you can't delete a file from the repository; only make it not part of the latest revision.  The repository keeps the monster for all eternity, in case anyone ever wants to recall the state of the repository for that date or revision number.  </p>

<p>Is there a way to really delete that monster file  and end up with a decent sized repository?   I've tried the svnadmin dump/load thing but it was a pain.</p>

To permanently delete monster files from a svn repository, there is no other solution than using svnadmin dump/load. (
SVN Book: dump command
)
To prevent huge files from being committed, a hook script can be used. You could have, for example, a script that ran "pre-commit" whenever someone tried to commit to the repository. The script might check filesize, or filetype, and reject the commit if it contained a file or files that were too large, or of a "forbidden" type.
More typical uses of hook scripts are to check (pre-commit) that a commit contains a log message, or (post-commit) to email details of the commit or to update a website with the newly committed files.
A hook script is a script that runs in response to response to repository events (
SVN Book: Create hooks
).