Honeycomb Trellis is very complicated but once finished, it is absolutely gorgeous and is great on large panels like blankets, pillows, and even in scarves and hats.

Special Abbreviations
1 over 2 Left Purl Cross: 1/2 LPC
1 over 2 Right Purl Cross: 1/2 RPC
The first way
1/2 LPC: Slip next st to cable needle and hold in front, purl 2, then knit 1 from cable needle.
1/2 RPC: Slip next 2 sts to cable needle and hold in back, knit 1, then purl 2 from cable needle.
The second way
1/2 LPC: Drop next st off needle to front of work, knit 2, then pick up dropped st and knit it.
1/2 RPC: Slip 2 with yarn in back, drop next st off needle to front of work, slip the same 2 sts back to left-hand needle, then pick up dropped st and knit it, purl 2.

Knitted in a multiple of 6 sts and 8-row repeat.
Row 1 (Right side): P2, * k2, p4; repeat from * to last 4 sts, k2, p2.
Row 2: K2, * p2, k4; repeat from * to last 4 sts, p2, k2.
Row 3: * 1/2 RPC, 1/2 LPC; repeat from * to end.
Row 4: P1, * k4, p2; repeat from * to last 5 sts, k4, p1.
Row 5: K1, * p4, k2; repeat from * to last 5 sts, p4, k1.
Row 6: P1, * k4, p2; repeat from * to last 5 sts, k4, p1.
Row 7: * 1/2 LPC, 1/2 RPC; repeat from * to end.
Row 8: K2, * p2, k4; repeat from * to last 4 sts, p2, k2.