The wind tunnel model of the Belco Avia.
 
Belco Avia are an Italian company that specialise in composites, amongst other projects they build racing powerboats, manufacture bodywork for sports cars and they did the composite work for the F1 Forti team. They announced their F3 car at the end of 1998 and showed the above model and stated they would begin testing in January 1999 but to date I have found no evidence that the car was ever built or raced.