I'm wondering if anyone knows of a product like this but that is physically mountable internally rather than on a cable?

I'm planning on building a super low profile "gateway" pc that is dedicated to handling internet traffic in my home. I have a great 1U rackmountable chassis for an ITX motherboard, but I need the hard drive real estate for the additional NIC required to run a gateway (one onboard and one PCI).

So the plan is to use a small 8GB USB Jump Drive for the OS inside the box (as to not have one hanging out the back. And although it's racked, I still don't want the jump drive flopping around internally, so I want it fixed somehow. I have an alternative idea where by I use a flush mount zap strap saddle and a zip tie to hold it in place, but that seems kind of like a hack.