Convekta offers a number of valuable CDs for those of you that are interested in well-annotated game collections. Currently, they have CDs on the following world champions: Alekhine, Capablanca, Lasker, and Botvinnik.
These CDs are mostly intended for intermediate players and above. While annotations are in Informant codes, they are typically very detailed. Important plans and positional elements are discussed, along with full analysis of important continuations. This analysis was performed and compiled by a team of IMs and GMs working with Convekta. Many games also include relevant analysis from other World Champions as well. If you want an example of the kind of detail you will find on these CDs, check out the screen shot below. This kind of annotation is unequaled among any other software currently available. For those of you not familiar with Informant codes, some important ones are the triangle (meaning 'with the idea'), and the thing that looks like a half-circle (meaning 'better is').
There is also usually a short biographical piece about each world Champion, along with complete tournament crosstables and photographs. Below is a screen shot from the Capablanca CD.
Each CD also includes a selection of test positions, organized by theme. These themes highlight areas where that player was particularly strong (for instance, Tal's attacking style, and Capablanca's positional play). Once again, these exercises are typically geared toward the intermediate to advanced player. The exercise below is an example of one of the test positions from the Lasker CD. Most of the exercises are on the difficult side, and will be a challenge for just about anyone, even those with ELOs over 2000.
All the features of Convekta's famous interface (as used in CT-ART) are present in the test software as well. This includes such features as complete statistics on each theme, and a running estimate of your playing strength. You can even play against a chess engine from any of the test positions, if you want to try out alternative continuations.
At the price, these CDs are a true bargain. Each contains over 1000 annotated games, and hundreds of test positions. If you can read Informant codes (and it is not hard), then you will learn quite a bit from these CDs.