I agree with your sentiments re: relative security.
Everything is relative and whilst VPN may be preferable/advantageous, frankly it doesn't suit all purposes (eg accessing via a mobile phone).
"the best way to get to your data while on the road is via a VPN or a dedicated"
I'd suggest "best" be changed to "more secure"...you don't consider what my requirements are.
The topic covers a straightforward means of password-protecting the NAS box using the tools commonly at hand....not ideal...not in a secure server farm and I also don't have a rottweiler patrolling the fenceline (the fluffy cats that get hungry...that's another matter

beware anyone that breaks in without bikkies ).
I'm also not dishing out the files to all..just personal use/friends *** on an adhoc basis ***.
As an aside, Aprelium has features to deter hacking attempts...
http://www.aprelium.com/abyssws/features.htmlWhether or not the XP box has Aprelium installed, the susceptibility to rootkits/trojans already exist for any client on the LAN, potentially exposing NAS shares from the LAN.
Likewise a poorly configured linux box or mainstream web server package is also a risk...or even one not fully updated/patched or a popular target for hacking.
Ultimately, pulling every cable from the NAS box (including power) and upgrading the hungry fluffies to aforementioned rottweiler's would also achieve greater security at the expense of functionality.
But given the requirements this is one solution that provides "adequate" security to share Naslite beyond the router and front door. A topic that is often raised re: NASLITE..."how do I password protect my shares."