I've had two ideas for MOBOs that I've always wanted implemented.
First, like a couple people have mentioned, an ultra-stripped non-standard-backplane motherboard for modders. It'd be MicroATX or ITX in nature, but it'd be no taller than a RAM module. EVERYTHING on the board would be flush with the top of a RAM stick. It'd have only the essentials. only one PCI-X16 slot, nothing else. ONLY SATA, no IDE/Floppy/Anything. ONLY USB3.0, no FireWire/USB2.0/PS2/Com/LPT, and so on. The back plane will be 4 stacks of USB (with 2 stacks available for the front,a nd MAYBE a front-plane FireWire port). The audio would be provided with an integrated X-Fi. There would be a Red/blue/green and an Optical on the back-plane, a header for front-plane, and then a break-out internal connector for the other analog points on either a 5.25 or (even better) a pci area back-panel bridge. There would ONLY be an HDMI (with bitstreaming, preferably) port, nothing else for video. Stacked ontop of that would be a SINGLE eSATA point. So, the back plane would, essentially, be a horizontal audio stack, 4 USB stacks, and then a combination HDMI/eSATA stack. And that's it. Internally, there'd be a header for front-panel USB/Audio, a header for a break-out box for the audio, and SATA jacks, and nothing more. No networking, no Wireless or bluetooth, nothing. So, you'd be looking at a board that is no thicker than a ram stick, with a single PCI-X card slot for potential graphics card. It'd have the VERY basic inputs of USB, video, and sound. The point? For someone who likes to mod (like me) or someone who just wants to use ultra-slim cases. The point, for me at least, would be to gut out a DVD/Blu-ray player, and replace it's internals with a PC instead. It's not really very hard at all (I've taken measurements, and there are even a few websites/forums that explain how to take a set-top's DVD/Bluray drive, and wire the pins into like a SATA, IDE (which can be converted to SATA with a box), and failing that, SATA laptop drives are plentiful and easily modded). The stripped down nature, and plethora of USB, is because you just don't need all that crap when the point of the box is to be a set-top player. network? USB. You don't want antennas and so on sticking out the back, you want to be able to hook a USB extender and set something up for better reception. Extra Storage (beyond the SSD or laptop drive that'd probably be used)? USB. think of anything you need. It comes in USB lol. And HDMI is home theatre friendly. Why the PCIX port? Because you may need it for a GFX card. I've seen a lot of people that make the PCI-X16 90deg angle converter for modders and the like. If you wanted to go all out, you could. Same with audio. But yeah, that's my first idea. I think that'd be SO hype for the modder community, and it would be solid BITCHIN for OEMs, too, because they could build ultra-slim, powerful PCs the size of a very thin set-top box. it'd keep costs down, because I imagine that the board wouldn't be expensive (cutting out a lot of superfluous stuff would keep costs WAY down), and by being so small and versatile, it would be super-easy to integrate. Hell, at that basic level, you could even have it find it's way into high-performance servers. Similar to like 1U racks, you could build clusters of small, paper-thin servers for amatuers who don't have the money to afford Racks and Rackmounts... I've just always thought a super-duper ultra-thin micro/itx board targetted at end users and not servers/OEMs would be dope.
My other idea is a little different tack, but in similar vein. Essentially, it'd be for a specific segment, primarily overclockers. essentially, it'd be a modification on the Socket. What you'd do is develop a "cartridge" mechanism. For people who change out their CPUs regularly because they like to upgrade, or just for easy system building. Essentially, instead of the basic LGA 775/1155/1366 socket, it'd be a specially manufactured contact probably just a copper-to-copper contact area (maybe with increased surface area) instead of the verticle pins. This would have a specially designed bracket to hold on a specifically designed cartridge. The cartridge would clip in a CPU, and then let you mount on a (standard) heat sink or water cooler contact. You would then just "clip in" the CPU cartridge after everything is settled, and boom, off you go. This way, for people do do lots of modding and testing, or people who are always upgrading, you have a low-impact, quick way to swap in and out heat sinks, CPUs and so on. It'd be great for testers especially, because it'd reduce the wear-and-tear on the LGA grid substantially, allow for quick and easy upgrades, and it'd be better for cooling, too, because, theoretically, you could make the mounting bracket out of aluminum, connect it to grounded points on the board, and have it double as a cooling array for capacitors/voltregs, too.
-E