Is using "needing" correct?

That's the man needing some money

is correct and means

That is the man who is in need of some money.

Most grammar textbooks tell us that verbs of opinion/preference/necessity cannot be conjugated in the BE+V-ing form. Why, they say ? Because it's the "Present Continuous" and therefore verbs that express not an action but a quality of the subject cannot be put in that form as that would be illogical : states are inherently continuous putting the verb in the "Present Continuous" would be redundant (and we all know that language is never redundant, right ?).

Most grammar textbooks are wrong and haven't been written by linguists.

If what they say were true, then the following verbs would NEVER be found conjugated with BE+ing : think, have, like, love, need, ...

Now look at these examples : "You know what, these days I'm thinking more and more that ..." "I'm having none of that !" "I'm loving it!" "This page is needing clarification." "You're being silly!"

So what's the problem with the grammar ? Well, it starts with calling "Present Continuous" a form of the language (here : BE+V-ing) without looking at all of its possible uses. Sometimes the verbal form with BE as an auxiliary + the verb with an -ing ending does indeed mean that the action is present and taking a bit of time, but there are many uses of the form that are neither present nor continuous :

Example 1 : "What are you guys doing tonight ? -Oh, we're thinking of going to see Blockbuster XYZ."

Example2 : "John and Sue are finally getting married. It'll be on September 5th."

In both of these examples what is expressed is a decision that's supposed to take place at some future time (That's called in grammar books "Present Continuous with a future value". Now if that doesn't sounds confusing to you, what does ?)

What the form BE+V-ing really does is to indicate that the action or state refered to by the verb in question is presented by the person speaking as actualized (that's the mental operation marked by the suffix -ing) and that this actualization is intimately linked to the situation under consideration (which is the core value of the verb BE). In other words : the action/state is specifically true in this situation to the (possible) exclusion of other situations.

Now that can translate into many things, such as actions that are underway now (present continuous), decisions that have been taken (but might have not been), things that are unusual, things that will take place because of a present decision, or things that the person speaking judges of negatively (I observe it, and I'm not happy about it)...

So, If a page needs clarification while most other pages don't (or if the speaker thinks it ought not to) the the page might "be needing" clarification.

If you always thought you'd never love it but suddenly you find out that contrary to what you think should be normal you do, then you're "loving it".

And if you act in a silly manner but that's not your normal way of being, then you might get told that you "are being silly"...

This explanation was brought to you by the Theory of Enunciative Operations, a branch of linguistics that's popular in Europe (especially in France, where it was created by a professor named Antoine Culioli) but not so well known in English-Speaking countries.