Lain's new NAVI as of Layer 02.
By Layer 03, Lain's NAVI has already shown extensive modification.
In Layer 06, even more hardware has been added, along with a liquid cooling
For most of the anime, Lain uses the new NAVI that her father bought for her upon her request in Layer 01. She receives it from the delivery man in Layer 02.
In Layer 03, Lain receives a Psyche processor from JJ that she later attaches to her NAVI. This allows her to access the Wired without a device.
Lain's NAVI eventually grows to fill her entire room, expanding to include a complex cooling system, several holographic screens as well as normal ones, and large numbers of cables. Notably, a pressure gauge on the cooling system is stamped with "mebious.co.uk", a URL that has been registered by a fan of Lain.