Megaprims, a Second Life building exploit that's led to amazing content like this Light Waves statue at left, has been banned by the Lindens for nearly two years. The concern with megaprims, programmer Qarl Linden explains on NPIRL's blog, is griefing on the mainland. "With the current code, a Resident with a 1x1 parcel could erect a sim-wide banner." However, he also offers a solution: "[A] VERY easy way to solve this problem is to make mega-prims an estate option. Estate managers can chose whether to turn them on/off -- and then can personally deal with any issues that may arise."
Quick as a wink, Dirk Talamasca created this JIRA MISC-3450 feature request, which you can vote on if you see fit. Image via npirl.blogspot.com