I have been scribing the notes of certain subjects systematically. The first was with Complexity 2 by Arvind and it really helped. I then volunteered to scribe Algebra and Computation by him in the next semester and now am scribing Computational Number Theory, a course I'm taking at IITK. The notes are available here:

• Complexity Theory 2 (Aug-Dec 2006)

  This is one of the courses I took up in my 5th semester of my BSc. This was taken by Arvind and we covered quite a lot of "cutting-edge" stuff in it.
  There was a first round of scribing that we did, I think we covered roughly 7 lectures in that. Then we covered more on error correcting codes and went into extractors.
  The lectures on expanders that followed after a while excited me and I decided to scribe them myself, and also the following lectures on the PCP theorems.

  We then had a lecture on Expander Codes, and then discussed Razbarov's lower bounds on monotone circuits for clique. In the final class we discussed depth lowerbounds for monotone circuits evaluating matching.

• Algebra and Computation (Jan-May 2007)

  In my 6th semester of my BSc, I had taken up "Algebra and Computation" by Arvind and I scribed the notes systematically.Shreevatsa, Vipul and Kazim had also offered to help me in scribing, some of the lectures were scribed by them.

• Computational Number Theory (Aug-Dec 2007)

  This is a course I have taken at IITK for my MSc credits in CMI. It is offered by Piyush P Kurur. The notes are quite detailed. I missed the first few classes of this course where he discussed the extended euclid's algorithm and an introduction to groups, fields, rings.

• Computational Complexity (Aug-Dec 2007)

  This is a course I have taken at IITK. It is offered by Manindra Agrawal. I decided to scribe the notes of the PCP theorems, extractors, expanders etc. Though these were covered in the course by Arvind (complexity 2), it is useful to have another perspective as well.