I'm looking for a scope around 100MHz with 4 (or more ) floating AKA isolated AKA differential inputs. I'm aware of Tektronix TPS2000 & THS3000, Fluke 190-104,-204,-504, and the crappy PC-based offerings from TIEPIE and PicoTech. Am I missing anything? I've searched extensively and I'm pretty sure that what I listed above are the only current products out there (correct me if I'm wrong) so I guess I'm looking for obsolete used equipment that's no longer advertised. Think back; can you remember coming across one in days gone by, that might be had on eBay? Handheld or portable form factor preferred.