Moving though space relative to space itself (imagine space as a 3D grid in wich we are all moving). My point is that wel are all eventually moving though space at 0.01% speed of light (lets asume that number true for the sake of argument). If we would have a speed of 0% of speed of light (full stop) then all other objects would keep moving such as a satelite in orbit stopping in space would then move away from Earth (or crash into it) relative to us. I dont know if it was done but if we had a detector that fires 6 lasers from all 6 directions (up,down,front,back,left,right) and measure the difference we could know the speed wich Earth is traveling though the universe, relative to Earth we wouldnt move but we would still be moving around the sun around the galaxy moving away from other galaxies.
If we accelarate a spacecraft with such detector and try to make him move into such a speed/direction that all 6 lasers would collide at same time that craft should be considered stopped in space. I dont know if this makes much sense >< I dont know how could this be useful tho ;p
Now that you mention massless particles moving at infinite speeds it reminds of a game called Mass Effect. Good game but there is an idea in it that if we could remove the mass then an object would move at infinite speeds. Of course we could remove not the whole mass but, say, 99% so then we could propel an object 99% closer to infinite (lol). Problem is bending the space, not with some exotic matter or drawing pretty wormholes. Im trying to get a sollution by affecting the space around with mass/speed/magnetic fields. Would it be possible to have a spinning ring (affectable by magnetic fields) that is held together by a magnetic field focused on attracting it inwards to counter inertia so it could be spin more quicker without destroying it? The ring would hopefully be as heavy as possible.