Skill advancement systems

[hymer]

I'm feeling a little sluggish. Please help me think of ways skill systems work. I know the following (and these are the examples):

1: You gain new skills with levels. Individual skills don't improve easily, but are pretty much equal to your ability stats with relatively small variations (2nd ed. AD&D).

2: You gain skill points with levels. Your ability stats affect the skills, but skill points invested will tend to be the bigger part of your skill stat in the end (D&D 3.X).

3: You gain a little in every skill as you level, your skills are affected by your ability stats, and you can shore up the skills with other choices (SW Saga).

4: You advance skills, which becomes harder the better you are. Your skills are greatly affected by your stats (Cyberpunk 2020).

5: You advance skills, which becomes harder the better you are at them. Your skills are somewhat affected by your stats (CoC - don't remember what version).

[Altair_the_Vexed]

WoD is sort of a half-way house between CP2020 and CoC: your skills are moderately affected by your stats.
Also, that sort of skill system works in a non-linear resolution: you gain more chances (dice) with each skill point, which increases the potential impact of your success.

[The Rose Dragon]

You buy skills with points, which do not necessarily come with levels, which are always the same cost to buy one level in (Mutants & Masterminds).

[Anonymouswizard]

There are also systems like savage worlds, where you can occasionally gain a couple of skill points, and skills are not affected by your stats, but stats do acct as a soft limiter.

[Jay R]

You gain abilities at the start of the game, or by finding a teacher and taking time to learn. Your skills start at a level based on a character ability, and improve only by being used effectively (Flashing Blades).

[Gwazi Magnum]

D&D 4th edition you start off with skills heavily dependent on which you choose to focus in and your stats. But the higher leveled you get the more equal the skills become.