Running out of space, thoughts?

Growing six Maple Leaf Indicas (Sensi) from seed and have hit a bit of a snag three weeks in... Everything had been going/growing very well, vegging in a Homebox L (3x3x6), 400W MH. The four early risers are now in 5 gallon square pots (their permanent home), while the two who got a late start are in 8" pots and need to be transplanted soon. THe problem = where do they go? Right now, the 8" pots fit on the side of the tent, right against the edge, but I couldn't place them into bigger pots and still fit them inside the tent.

My options are

1) Give to friend to veg under floros (in attic space, not enclosed, heat is fine, ventilation is fine. I would bring them back to the tent once I've gotten rid of some males.

2) I have heard of people stacking with transplanting, for instance, placing this 8 inch pot into another 8 inch pot so the roots and just grow down and not out. This still seems like it would cause problems as the leaves start to broaden.

3) Something better?

Any helps is appreciated.

option one seems fine....but I would just leave them in the tent. flower and once sexed i would do a late transplant once males r weeded out.

I have seen people growing in trash cans on here before. Go to walmart and see if you cant find one narrow enough to fit your space but taller than the 8" pot. You may not get room side to side but the roots will have more depth to stretch into.

The trash can idea worked perfectly! We are now in week four flowering and although the plant is slightly smaller, she seems to be doing just fine in her 3 gallon garbage can...I shall call her, "Oscar."