Can NOT take back rezzed object

Hi. I got a box of freebie stuff and one of the items was called "alien cloud", so I pulled it to the ground to see what it was. It's like a small purple smoky particle campfire or something. The thing is, I can not take it back to my inventory. I have tried right clicking all around it but it never takes.
Then I remember seeing or reading something about how you can "look into" a solid object to see if any items are lost there but I forgot how and can't find that info again. Can someone please tell me how to get rid of that puff of smoke that using up prim space?
Btw, I have already logged off and back on but it's still there. HELP?!?!

Turn on "Highlight transparent" in the View menu. There is probably a very small and invisible prim that is the source of the particle effects.

Hi Tianti, try clicking control/alt/t (or it might be command/alt/t - I'm a Mac user, so I always get confused what it is for PC users!). Doing that will show up the full boundary of the item in red, and you should then be able to click on the item and retrieve it in the usual way. Press control/alt/t again to get rid of the highlight. Also, it's worth checking out the knowledge base for other neat tricks, like making the ground 'disappear' if you accidentally bury something in it! Good luck.

Aah... looks like Ceera just gave you the same answer without using the keyboard commands