<p>I'm planning on doing more coding from home but in order to do so, I need to be able to edit files on a Samba drive on our dev server. The problem I've run into with several editors is that the network latency causes the editor to lock up for long periods of time (Eclipse, TextMate). Some editors cope with this a lot better than others, but are there any file system or other tweaks I can make to minimize the impact of lag?</p>

<p>A few additional points:</p>

<ul>
<li>There's a policy against having company data on personal machines, so I'd like to avoid checking out the code locally.</li>
<li>The mount is over a PPTP VPN connection.</li>
<li>Mounting to Linux or OS X client</li>
</ul>

Use a source control system — Subversion, Perforce, Git, Mercurial, Bazaar, etc. — so you're never editing code on a shared server.  Instead you should be editing a local work area and committing changes to a repository located on the network.
Also, convince your company to adapt their policy such that company code is allowed on personal machines
if
it's on an encrypted volume.  Encrypted disk images that you can use for this are
trivial
to create using Disk Utility, and can use strong cryptography.  You can get even more security by not storing your encryption passphrase in your keychain, and instead typing it every time you mount the encrypted volume; this means that even if your local user account is compromised, as long as you don't have the volume mounted, nobody else will be able to mount it.
I did this all the time when I was consulting and none of my clients — some of whom had similar rules about company code — ever had a problem with it once I explained how things worked.  (I think some of them even started using encrypted disk images even within their offices.)