Figured it could be nice to keep a list of Qt/KDE apps that can help fill the gaps in Haiku’s software line up for the time being.
Scribus, desktop publishing application.
Hydrogen, drum machine.
Rosegarden, sequencer/score editor.
Qtractor, digital audio workstation.
FreeCAD, CAD tool.
LyX, LaTEX editor.
…are all ones that stand out off the top of my head. Any others?
I’d suggest trying to port them. The only problem with some of them (Hydrogen, drum machine; Rosegarden, sequencer/score editor) is they might be very dependent on Linux, so great efforts might have to be made to make them compile and run on Haiku.
The only way you will know is if you try though 
Well, Traverso (THE open source/multiplatform multitrack audio recording and editing suite) should be simpler to port !
Check this 3ad @ their forum…
BTW, a native tool would be even better: so why don’t improve Hyperstudio (or BeAE) ?
“so why don’t improve Hyperstudio (or BeAE) ?”
yes, why don’t you improve hyperstudio?
I also hope, that after Qt 4.7 will be ported to haiku, also new qt-applications will follow. I use for example LyX very often. Porting LyX on Haiku, would than mean, that I spend a lot more time using haiku. But I guess this is not so easy to port. I would also donate money to a bountry, if someone would port it.