If I remember correctly there are some going to Budapest in April / May. We will be there the 1st through the 10th (I know, too short, buy I have to work). We have a guest this time so I've begun looking for things to do to make it special for her.
So far I've found:
great concerts at Opus Jazz Club, MUPA and Budapest Jazz Club.
Falk Miska utca has an event to showcase the art galleries and antique shops; with food and music in the street on the 5th of May.
The Saturday morning farmers market at the Hunyadi ter market hall is always an experience as are the vendors Saturday and Sunday at the Gozsdu udvar.
I'll post more as I find it.