Tips I can vouch for:

• What to do with that last fiddly stitch when binding off. when knitting flat.
• Cat Bordhi demoing Judi’s Magic Cast On 
• Knitting backwards – without twisting your stitches. I just don’t see the benefit if I have to remember to knit thru the back loop on the right side.  
• Knitting in the round “Close the Gap”
• The Yarn Harlot’s (Stephanie Pearl McPhee) technique for tightening a baggy neckline .  
• New sock heel everyone is raving about – the Fish Lips Kiss Heel by Sox Therapist. In my opinion, this is the best $1 you’ll ever spend if you knit socks.  
• Weaving (knitting) in ends as you go
  • Version 1: video from Carol Feller/Stolen Stitches.  Continental technique starts at about 2:10.
  • Version 2: video demo from Staci Perry/VeryPink Knits.  Staci doesn’t show a continental version.
• Fix a multi-row hole in knitting tutorial from Patty Lyon.
  • Alternate skeins using the helical knitting technique (slipping stitches) demonstrated by Grace O’Neill.

I haven’t tried these but want to share them anyhow:

• More complicated knitting backwards demo which has multiple stitch types
• Patty Lyon’s Seaming a set in sleeve.  This has been recommended by several Yarniacs.  
• Fixing German Short Rows video by Roxeanne Richardson.
• Swatch for knitting in the round. This technique doesn’t end result in long floats in the back.
• Other methods for alternating skeins:
  • Drop yarn and swap demonstrated by TKGA Master Knitter Suzanne Bryan
  • Slip 3/knit 2/slip back and knit slipped stitches. This is a Raverly forum post so you have to have access to Ravelry to see this one. Tweaking the number of stitches you slip should make this work with many different stitch patterns.