Name one. I've searched CyanogenMod's supported devices page, and the earliest CM12 compatible device is from early 2012. Everything else is CM11 or earlier. MIUI v7 is similarly limited to devices from early 2012, AOKP hasn't yet released a stable Lollipop build for any device, and Paranoid only goes as far back as late 2012 / early 2013.
Near as I can tell, no Lollipop Rom supports anything from before 2012, mostly because the device manufacturers are still using proprietary blobs that require specific versions of the linux kernel to compile against, limiting how much support can actually be provided by newer versions of Android. There's also the fact of CPU/GPU/RAM limitations to take into account on older devices, and whether the experience of a Lollipop build for an older device becomes so terrible that it causes harm to the brand as a whole. Apple ran into that during their previous OS update to iOS 8, with the oldest compatible devices becoming noticeably slower after the upgrade.