Don't limit Drupal sales to just websites. We find that traditional websites make up a smaller part of our business even when they are quite large while innovative new setups from overlays on video on screens in franchise stores to large scale presentations and intricate real-time integrations make up more of our work.
Here's a system we built that presents social interaction live at concerts for real-time interaction by attendees on five multi-story screens (two of them visible in this article next to the stage). The same system is used in more formal settings too and applied here by a Germany-based company.
I don't often get to talk about the work we do ;-)
http://www.thenational.ae/thenationalconversation/industry-insights/medi...

Comments
Applications
I am also finding that clients pay more for "applications" than websites. I have just finished two of these - one is to manage Warranties and Claims for a large corporate (with workflow and access control), the other is an international support/helpdesk for a software company.
Both had very unique requirements, and companies who quoted custom development came in at R50k - R100 and up. Even an opensource solution came with a R70k "customisation and hosting" price tag.
With Drupal doing the heavy lifting, I gave them a very slick interface with advanced features they never thought they could afford, well within the deadline - and I made nice profit as well.
Unfortunately confidentiality agreements forbid me to boast about them, but I'm hoping they will tell all their friends about me :-)
There are 10 kinds of people in the world, those who understand binary and those who don't.
Whitelabel
Interestingly, most big projects do not allow you to or imply you do not talk about them. Never mind that your logo never goes on the bottom.
We hardly ever get an NDA, but have them ready for the occasional requirement. Still, mostly other people's logos go for attribution bottom, if any.
Like the guys from Acquia I'm averse to noting Open Source as cheaper than commercial offerings. We're often more expensive and mostly in the same price bracket, but we're a lot better in the customization front and our products end up being much more effective too as we spend that money that would have gone to licensing fees on better product development. Clients get a lot more bang for their buck with Drupal.
Something else I notice with some clients is that they lose confidence in a solution once you mention open source is in the back-end. I often only reveal that and the "Drupal" name after everything works very well, then they become great proponents of FOSS and Drupal.