Where is the best place to pitch ideas to Portable Apps developers?

I have a few ideas I think would make cool apps/portable apps...
Not real complicated stuff but stuff I think would have big niche appeal to quite a few people...(And if people are interested...developers and/or potential end users I would like to work with someone to get it done.)

I could go into quite a bit of detail but I don't want to waste my breath in the wrong forum of if people are not interested.... suffice to say, in a nut-shell these are:

1)a 2D old-style "karate game" construction app...
i.e a simple UI driven app that allows users to build their own 2D fighting games...

(with this functionality built into the app the creative potential of hundreds of thousands of people would be unleashed on this thing and it would go viral i'm sure of it.. it would be a blast)

Users would define:
- the size if their characters,
- all the graphics/animation (animations and graphics could be shared on line, perhaps with the ability to put celebrity heads on it ect)
- the frame rate
- attack and block maneuvers etc
- UI ie keyboard,mouse joystick actions required to execute moves.
- how many frames in each technique (speed)
- also define defense zones, attack zones and vulnerability zones on each frame (where required) these zones would define which parts of each frame had the potential to attack,block or be hit and also an attack/block point rating for each zone on each frame and a hit point rating for each vulnerability zone.
i.e contact would occur when an attack zone met a vulnerability zone or block zone and hit points sorted out...
and the graphics could be defined to change in controlled ways depending on the hit point score to any body part (vulnerability zone) and or which technique was used to execute the attack...
- the ability to control transparency of characters
(incase you design the camera angle to be 45 degrees ..ie for point of view style boxing games where you could fight online people.. instead of the standard side view)
- sound FX ect

2) my second idea is a poly-rythmic sound (drum) sequencer...
I.e there is many drum sound sequencers out there but almost none have the ability (in the context of a Basic UI) to define:
- number of instrument tracks.
- number of beats per bar for each track.
- the resolution of each beat!!! (anywhere)
i.e you could click on any beat then divide it into any number of subdivisions...

This would allow you unprecedented control... (ie not everything fits into a neat 8 divisions!

3) My 3rd idea is a palette reduction application which would allow you in a very quick way (with a slider and the ability to click tag... colours on screen or in a palette interactively as you move the slider up and down) to produce excellent vector style art from very fast (but controlled) palette reductions.