i finally figured out what this thing is! it's a part of a desk set, the hole was originally fitted with a pen holder and the bowl portion used to hold paper clips or the like.
this exact technique (of the piece originally in question, not the one pictured below) is found in "italian glass century 20", page 74. according to the book it was designed by Flavio Poli for Seguso Vetri d'Arte and "likely executed by Archimede Seguso". (the vase in the book is a 9.25" and is valued at $16-18K
my piece is under 4" but still...)
i've attached a pic of a similar piece that confirms it's function.