$ yaourt -Ss lego
aur/konstruktor 0.9.beta1-1 (8)
    A LDraw-based virtual LEGO(r) CAD for KDE 4.
aur/konstruktor-git 0.9.0.beta1.r78.g67ef13e-2 (5)
    A LDraw-based virtual LEGO(r) CAD for KDE 5.
aur/ldraw-parts-library 20131223-1 (20)
    A collection of LDraw-format CAD files representing many of LEGO bricks produced
aur/lego-udev-rules 1-1 (6)
    udev rules for the lego nxt
aur/legoirc-server 0.1-1 (0)
    LEGO IR Controller Server
aur/lejos-nxj 0.9.1.beta3-4 (8)
    A firmware replacement and toolchain for programming the Lego NXT in Java
aur/lejos-nxj-svn 6954-1 (1)
    A firmware replacement and toolchain for programming the Lego NXT in Java
aur/lejos-rcx 3.0.0rc2-4 (4)
    A firmware replacement and toolchain for programming the Lego RCX in Java
aur/leocad 0.82.1-1 (14)
    LeoCAD is a CAD program for creating virtual LEGO models. It has an easy to use interface and currently includes over 6000 different
    pieces created by the LDraw community.
aur/libnxt 0.3-2 (1)
    An utility library for talking to the LEGO Mindstorms NXT intelligent brick
aur/nqc 3.1.r6-2 (4)
    Not Quite C used to program Lego's RCX, with USB support
aur/nxc 1.2.1.r4-1 (6)
    Not eXactly C -- to program LEGO's NXT programmable brick
aur/nxt-python 2.2.2-3 (6)
    A Python driver/interface for the Lego Mindstorms NXT robot.
aur/nxtrc 2.3-4 (2)
    A tool for communicating with lego nxt brick over bluetooth
aur/ocaml-mindstorm 0.5.2-1 (0)
    A library for controlling Lego Mindstorms NXT bricks from OCaml
aur/t2n 0.5-3 (4)
    A Tool for communication between PC and Lego NXT over usb
aur/vim-nqc 3.1-2 (1)
    programming support (for the LEGO MINDSTORMS RCX-Controller)