I've had a handful of people ask me for specifics on this...read on, intrepid craftsters!
**DISCLAIMER: There's an unresolved question as to the wisdom of using static-carrying felted wool to cover an electronic device. Use this jacket only when the machine's not on, or proceed at your own risk**
I'm going to try and provide a discussion of the method I used to create and construct this, augmented by my notes for a 12" Powerbook, rather than a straight pattern. Since felting wools vary so widely, and because you might not have the exact same computer, a technique study might be more useful than a knit one purl two-type list of instructions.
1) Make a felted gauge swatch. This is absolutely imperative for two reasons: first, to make sure your knitted piece will felt to fit with holes and panels in the right places, and second, to make sure that colors and wools you might combine will felt at the same rate. A good way to do this is to knit a square incorporating each yarn you wish to use, say 30 rows by 30 stitches, and mark off a ten stitches and ten rows with a slippery cotton yarn. Wash the swatch until it forms a fabric you like, block and let dry, and measure the distance between the markers. I lucked out and got exactly 5 stitches and 10 rows to the inch. The following pattern is based on that gauge.
For the record, I used blue Pastaza, red, white and brown Manos, and dark grey Cascade 220.
2) Take measurements of every relevant plane. The absolute basics would be lenth, width, and height. Measurements for a snug-fitting jacket for a 12" Powerbook are as follows:
This diagram is SO not to scale it's not even funny.
3) Figure out how many rows and stitches will give you your measured diagram. For my laptop, I knitted the main top and bottom cover in one piece and knitted on all flaps before felting.
Beginning with a knit (RS) row, work in stockinette random stripe 86 rows
(RS) BO7 st, k4, attach new yarn, BO35, reattach yarn and k to end of row
Next row (WS): BO7st, work to end of row
Work 7 more rows in stockinette
Next row (WS): p7, CO35, p7, CO7 (use cable caston)
(RS) k to end of row, CO 7 with cable caston
Work 25 rows in random stripe before dividing for logo port
Row 27 (RS): k41, attach new yar, BO3, k41
Row 28 (WS): p to last 2 st of first panel; p2togtbl; p2tog; p to end of row
Row 29 (RS): k to last 2 st of first panel; k2tog; k2togtbl; k to end of row
Row 30 (WS): as row 28
Row 31 (RS): k all stitches
Row 32 (WS): as row 28
Row 33 (RS): as row 29
Row 34 (WS): as row 28
Row 35 (RS): k all stitches
Row 36 (WS): as row 28
Row 37 (RS): k all stitches
Row 38 (WS): p all stitches
Row 39 (RS): k all stitches
Row 40 (WS): as row 28
Row 41 (RS): k all stitches
Row 42 (WS): p all stitches
Row 43 (RS): k all stitches
Row 44 (WS): p all stitches
This completes one half of the logo port. Continue, reversing shaping (that is, follow the rows in reverse order, from Row 43 to Row 27, and make 1 where directed to decrease.
CO3 st at the end of the first panel after the last increase row.
ALTERNATELY, work the top panel straight and cut a hole after felting (the fabric won't unravel).
Continue until 86 rows total have been worked for top panel.
Pick up and work one row of trim around perimeter of knitted piece. Pick up stitches at a ratio of 1:1 for horizontal sections and at 1:2 for vertical sections (pick up 1 stitch for every 2 rows). BO.
Work corners by picking up stitches around the corner and working straight for 7 rows before binding off. Corner should turn up automatically.
Pick up and work 10 rows for top flaps. Bind off.
3) Felt the piece carefully in hot water, checking often and adjusting as you go. The hole in the center may need to be pulled to shape several times during shrinking...I went through about 3 wash cycles before the piece satisfied me.
4) Seal the notebook itself in a gallon ziploc or in many layers of saran wrap, and block the jacket around it, pinning it to itself as fit is achieved. You will need to stretch and pull to get a perfect fit.
5) Attach elastic to the top and bottom corners to keep the jacket on during use.
I know these instructions are still a little vague, particularly around the corner and logo hole shapings, mostly because I did this on a whim and didn't keep extensive notes as I made it up going along. I'm happy to help anyone who'd like more details, though!