Share USB over IP (LAN or Internet) and use it from a remote location. You can share various devices, including as MFD, scanners, webcams, etc. These USB devices will be accessible at a remote computer as if they were connected to it directly.
USB Network Gate (former USB to Ethernet Connector) establishes a passthrough of USB devices from the host system to guest OS on a virtual machine. As a result you can easily use USB devices on a virtual machine as if they were connected to it directly. USB Network Gate supports VMware ESX/ESXi, Citrix XenDesktop, and Microsoft Hyper-V.
You can offer remote support for your clients' USB devices no matter how far away your clients are. They just have to share the USB device so that you can access it with the help of USB Network Gate and resolve any issue asap.