The full text of the CC by-sa 2.5 license says:

http://creativecommons.org/licenses/by-sa/2.5/legalcode

"You may distribute, publicly display, publicly perform, or publicly digitally perform a Derivative Work only under the terms of this License, a later version of this License with the same License Elements as this License, or a Creative Commons iCommons license that contains the same License Elements as this License (e.g. Attribution-ShareAlike 2.5 Japan)."

My personal opinion is that this renders the sa CC licenses viral: there is no such thing as a "compatible" license, because the share-alike requirement is that one of an enumerated set of licenses is used, not just "any license with similar terms". Whether your work is a Derivative Work or not depends on what you've copied - seeing a copyrighted implementation of bubble sort doesn't necessarily mean you can never use bubble sort again. If it's not a Derivative Work then the CC license is irrelevant, so you can distribute your work under any license you want, including MIT.

However, I am not any kind of lawyer, and certainly not your lawyer, so my personal opinion is worth what you're paying for it.

Note that CC Deeds (the thing you see when you follow the link in the corner of the page) each have a really tiny link at the bottom, behind a door marked "beware of the leopard", leading to the actual license.

[Edit: I have just added the following text to my userinfo:

"All my original contributions to StackOverflow are placed into the public domain. If this is not legally possible, then anyone receiving a copy of them by any means is granted a non-exclusive perpetual license to use, distribute and modify them, and to distribute modifications, under any license or none, with or without attribution to me. Please note that this license applies only to my original contributions."]

The full text of the CC by-sa 2.5 license says:

"You may distribute, publicly display, publicly perform, or publicly digitally perform a Derivative Work only under the terms of this License, a later version of this License with the same License Elements as this License, or a Creative Commons iCommons license that contains the same License Elements as this License (e.g. Attribution-ShareAlike 2.5 Japan)."

My personal opinion is that this renders the sa CC licenses viral: there is no such thing as a "compatible" license, because the share-alike requirement is that one of an enumerated set of licenses is used, not just "any license with similar terms". Whether your work is a Derivative Work or not depends on what you've copied - seeing a copyrighted implementation of bubble sort doesn't necessarily mean you can never use bubble sort again. If it's not a Derivative Work then the CC license is irrelevant, so you can distribute your work under any license you want, including MIT.

However, I am not any kind of lawyer, and certainly not your lawyer, so my personal opinion is worth what you're paying for it.

Note that CC Deeds (the thing you see when you follow the link in the corner of the page) each have a really tiny link at the bottom, behind a door marked "beware of the leopard", leading to the actual license.

[Edit: I have just added the following text to my userinfo:

"All my original contributions to StackOverflow are placed into the public domain. If this is not legally possible, then anyone receiving a copy of them by any means is granted a non-exclusive perpetual license to use, distribute and modify them, and to distribute modifications, under any license or none, with or without attribution to me. Please note that this license applies only to my original contributions."]