Thank you to Richard (9G5AR) for writing in and sharing with us a program he's developed called "RadioSport SDR". RadioSport SDR is a portable, no-install-required SDR program compatible with RTL-SDR devices. Richard writes that it is small and fast enough to be run off a USB stick.

The software supports demodulation of wideband FM, narrowband FM, AM, USB, and LSB modes. It also has a noise reduction feature.

The software can be downloaded from its GitHub release page here.