There are two plugins that I think should be made part of the core wordpress installation:
Limit Login Attempts
It seems to me that so far security has not been a major focus for the core wordpress engine. There are a few quite glaring security issues that should be fixed in a bare minimum installation and not require John Doe to know (and care) about security and the relevant hacks to try and fix them.
Limit Login Attempts seems like the most obvious option when trying to stop brute force hacking attempts (given that the login urls are common knowledge and it needs a fair bit of hacking to hide them).
Easy to use plugin which stops repeated login attempts, optionally logs the IP and blocks renewed attempts for a configurable amount of time.
Unattach
If anyone else played around with the media library and clicked the link "Attach" for an image just to see what would happen, he or she would have been equally stuck with whatever choice was made at the time, since there is no simple "Unattach".
Googling brings up a long list of post on this topic with various explanations on how this feature is meant to work and why there is no default unattach. None of them satisfactory though. Delete and re-upload was the common consensus.
Or install Unattach which adds a nice and intuitive "unattach" link to any attached image.
