Raffaele Rialdi pointed out that attempting to run RTF Host from Compact Framework 3.5 Power Toys on an emulator produces the following error:

This is caused by RTF getting confused because the default CoreCon transport on the emulator is DMA (DeviceDMA.dll). Here are the steps to add emulator as a manual Tcp connection. Not that many will need it, but it is useful for a demo

1. Start Emulator using Device Emulator Manager.
2. Configure Network and Storage card folder
3. Copy to storage card folder the following file: "C:\Program Files\Common
Files\microsoft shared\CoreCon\1.0\Target\wce400\armv4i\TCPConnectionA.dll"
4. In File ExplorerNavigate to \Windows\Corecon1.1. If you don't see it
there, connect to the emulator from Studio
5. Launch ClientShutdown (you should see a guid-named folder to appear)
6. Copy \Storage Card\TcpConnectionA.dll to \Windows
7. Go to \Windows and delete DeviceDMA.dll (if you can't, you forgot to
launch ClientShutdown)
8. Go back to \Windows\Corecon1.1 and launch ConmanClient.exe
9. Launch RTF Host. Enjoy