Once upon a time, Jamie Zawinski said,

Some people, when confronted with a problem, think, “I know, I’ll use regular expressions.” Now they have two problems.

BTW: Jeffrey Friedl dug into the history and found that someone said it about awk before jwz said it about regular expressions!

I seem to have developed a fascination for new variants of this joke, especially where the concept being referenced is important to the structure of the joke. For example, last June I said,

Some people, when faced with a problem, think, “I know, I’ll use binary.” Now they have 10 problems.

The other day I contributed,

Some people, when confronted with a problem, think, “I know, I’ll use threads,” and then two they hav erpoblesms.

It seems that Eiríkr Åsheim earlier had a similar one,

Some people, when confronted with a problem, think “I know, I’ll use multithreading”. Nothhw tpe yawrve o oblems.

Making fun of Java is easy. Chris Lonnen said,

Some people see a problem and think “I know, I’ll use Java!” Now they have a ProblemFactory.

Floating point can be surprising. Tom Scott quipped,

Some programmers, when confronted with a problem, think “I know, I’ll use floating point arithmetic.” Now they have 1.999999999997 problems.

Finally, this is not a technical joke, but is too true to leave out. Tom Dale said (and then deleted?),

Some people, wanting an escape from their full-time job, think “I know, I’ll contribute to open source.” Now they have two full-time jobs.

Brendan Berg has a list of others if you want more...