Sean the Baptist has a post 'And with two they covered their feet' in which he repeats the conventional wisdom that "feet" is (sometimes) a euphemism in the Hebrew Bible. Basically the idea is:

That is that the word for feet רַגְלָיו sometimes refers to what we might politely call 'other parts of the (male) anatomy'.

I have never really been convinced by the claim. Sean cites the following passages as the best evidence for this supposed usage (the order is mine, as are the comments in straight type):

Exodus 4.25 But Zipporah took a flint and cut off her son’s foreskin, and touched Moses’ feet with it, and said, “Truly you are a bridegroom of blood to me!”
Now why on earth would one suppose that "feet" here is a euphemism - after all no euphemism was used for "foreskin" עָרְלַת seems explicit enough.

Deuteronomy 11.10 For the land that you are about to enter to occupy is not like the land of Egypt, from which you have come, where you sow your seed and irrigate by foot like a vegetable garden.
In Egypt is most irrigation done by peeing? No wonder they brewed so much beer! Or maybe the small earth dams on irrigation ditches are quite easily broken by foot?

Ruth 3.7: When Boaz had eaten and drunk, and he was in a contented mood, he went to lie down at the end of the heap of grain. Then she came stealthily and uncovered his feet, and lay down.
If this one is a euphemism, does it not remove all the tension from the chapter where the most significant "gap" the hearer must fill is: "Did they or didn't they?" there is plenty of other innuendo in the chapter to build up the tension, without this (possible, maybe) one.

Isaiah 6.2: Seraphs were in attendance above him; each had six wings: with two they covered their faces, and with two they covered their feet, and with two they flew.
Really? Now why should face and feet not simply mean face and feet? Please explain!

Isaiah 7.20: On that day the Lord will shave with a razor hired beyond the River—with the king of Assyria—the head and the hair of the feet, and it will take off the beard as well.
Hairy feet or hairy [euphemism]? Which is more plausible? Though I suppose if the euphemism is for the whole genital area, this one might make sense.

Judges 3.24: After he had gone, the servants came. When they saw that the doors of the roof chamber were locked, they thought, “He must be relieving himself (literally 'covering his feet') in the cool chamber.” cf. 1 Sam. 24.3
At first sight, this one is good! In this sample I am almost convinced, there is a good case to answer, though why "covering his feet" should be a euphemism for peeing, and not merely another example of the rather gross schoolboy humour of the passage I am unclear.

2 Samuel 11.8 Then David said to Uriah, “Go down to your house, and wash your feet.” Uriah went out of the king’s house, and there followed him a present from the king.
Could be a euphemism, but then it could be that the sentence is euphemistic even if the "feet" are literal. "Wash your feet" = "make yourself at home"...

So, in the end, what evidence is there for this conventionally supposed common euphemism? Two cases where you might argue with some strength that reading euphemistically is the "best" reading, a couple more where it might just be possible but overall I'd say: No case to answer. In the Bible feet are just that. And Eglon as well as excessively fat, and greedy, also was known to his servants as having a poor aim. As the sign in our downstairs loo read for a while (we had teenage boys in the house) "We aim to please. You aim too, please!"