Try adding some features that make it look robotic. Wires, rivets, etc...
i would suggest using photoshop for pixelart... it has a lot of nice features, like seperate windows for 100% view, shortcuts for all the tools, which comes handy, also animation works quite well and adding transparency is no problem at all
A pile of rocks?
Any suggestions on how to Derock this pile?
I'll go download Giffy
Edit:
What am I saying? I'll just use Unfreeze and gimp, both of which I already have.
Junk junk junk junk junk. 
I'm sorry, but that was for your own good. As much as you'd like to, people just aren't always going to post 'what you want them to post'. Gotta accept that, deal with it, and move on.
Aside from that...
1) In order to show that it floats either A) Show some ground. B) Show some sort of way it floats, rockets, etc...
2) I 'm not really seeing a robot here. Just a pile of rocks.
edit:
Try a combination of GIffy to set the transparency and unFreeze to animate. I use it, it works.
I can't get my animated gif transparent.
I tried a program I had bookmarked, iaza, It messed up the animation when I checked "Add transparency".
I'll add in the animation, onek. Good idea.
AB, susu, stop posting junk in my pixel art comment page...
stop fighting guys... its kinda childish.... i dont think its necessary to curse , but i agree that its also unnecessary to give comments like ".. oh nice.." or "..thats boring.." etc. ... you should at least say why u think so, and, that way, help to improve,....
i like how u changed the shading, looks much better now, but why dont u add the animation?
Judging by your replies it is you who will shut up pretty soon...
Susu, could you do us all a favor and shut up?
I put a lot of time and effort into this.
You're calling me asshole because I called you LAZY, when you wrote that you didn't want to make it with legs becasue you were too lazy to make them.
I was just stating what I first thought when I saw it, it's really sad that when you don't like what others think about what you do, you decide to answer in an agressive and offensive way.
P.S: You did a really nice work editing what you've wrote before.
I already did one with hovering, I uploaded a single frame one.
Thanks for the example, and some actual C+C.
And susu, you should listen to onek.
be more polite... otherwise u wont make it long on this site ;D
this is very hard to read... lot of things seem to be in wrong positions, the shading is pretty much random.. looks more like rust or stains, try to define ur light source to modelate volumes, also magnets mostly have a red and a blue pole.. also u could add an animation even without legs, like hoovering, since it is a magnet robot...
heres an edit:
>>> http://i992.photobucket.com/albums/af45/oooonek/magnet_robot.gif
me neither ;D