Here's my TLS podcast about Hugo Ball's novel FLAMETTI.
The recording was interrupted by a Dada moment when the fire alarm went off and pre-recorded voices (one briskly male, the other soothingly female) insisted that this was not a drill, that it was a drill, that we should all leave the building, that we should not leave the building . . . and so on. You can probably tell from the panicky wobble in my voice the point at which the recording started again following the distraction.
My suggestion in the podcast (and in the accompanying TLS review) that one character in the novel, a condescending dandyish poet with pince-nez and 'lidless red rimmed eyes' is based on James Joyce has prompted no excited responses whatever. If it is a sighting it's really of great interest. There are to be sure many novels which manage to incorporate Joyce as a character, notably Flann O'Brien's wonderfully funny The Dalkey Archive. If it is indeed Joyce in Flametti it must be the earliest example of such an inclusion as a character in the work of another writer. Unless you know different? I can find no link between Joyce and Hugo Ball, or the Cabaret Voltaire, other than the fact that Joyce was resident in Zurich in 1916 when the night club was established.
About author sightings: a few months ago there was a a lot of interest in the discovery of Dylan Thomas milling around as an extra in a crowd scene in a film shot on Pendine Sands - read about that here. My favourite example of an author caught on film is the fleeting appearance of Raymond Chandler in Billy Wilder's Double Indemnity. This went unnoticed for half a century. Read about that and watch the clip here.