I'm trying to demonstrate to someone that one wireframe or template can be used across multiple brand experiences (we want the UX to be similar, but the brand experience to be different). At some point in the past, I found an article or blog post that showed multiple examples of "one wireframe, two/three designs", but I cannot find it any more. Anyone know of any resources - either actual websites or articles/blog posts/portfolios that demonstrate this?
If you're looking for a wireframe that's used in precisely the same way across different brands, then look no further. Either take one of the beta-stage StackExchange sites, e.g. GraphicDesign or just create a wireframe of an SE site yourself, and then show the dozens of graduated sites that use the same HTML across completely different brands, changing only the CSS. You have about 40 of them in the footer of this page. I really can't think of a better example. Best do it for both the list page and the question page.
Another solution would be to show how different the finished product can be of a wireframe, based on, like, wireframeshowcase.
Personally, I like to define UI in patterns, that is, to define what is the problem the user is facing, and what is a corresponding solution, and provide a lot of examples to it, rather than provide a single mockup, so that the developers can tailor those to their needs. One of my such UX docs was for an open source mail archiver (it's like GMail, except it's made sure you can't delete mails so a security audit could be done), albeit it's in Hungarian, but it's here if you wish. But sometimes developers want clean, finished, processed ideas, that is, they basically want a full-scale design which they just "type in".
UX is about patterns, and patterns are about problems and solutions: there's a need (like, we want the user to understand which button to press if everything goes normal) and there's a corresponding solution (we highlight a single "primary action" button), and that's it.
These patterns have to be assembled together in order to become an applicaton,for which the Wwreframe is merely an illustration, perhaps a test if this combination is able to work together or not, before the "real" design starts, as there are things for which font choice and color choice don't matter that much, and we want to concentrate just on the interactions / navigation.
If you concentrate on patterns instead of widgets and full-page wireframes, that can be assembled a lot of different ways, while still maintaining a similar experience across a family of systems.
On the other side, I don't see real design alternative checking in the industry, but perhaps I've only seen a small part closely. When I was doing web design, I did show 4 alternatives to the customers as a minimum, but I've seen too many times that designers come up with a single mockup, they toss it around a bit, then come up with a single visual design based on the mockup, then toss it around, sometimes making it radically different, and that's it.
One exception is Apple, where it's known that there are design teams to compete with each other with prototypes.