The yellow box you're talking about is simply alt text. It's a default feature of HTML. For example, you can use the following HTML tag to insert an image, where if you hover over the image, "alternate" text will appear.
<img src="file.gif" alt="Hover Text" />
I simply used alt within the td tag of my table. For example:
<table><tr><td alt="Hover Text">Table Row</td></tr></table>
will show the hover text whenever you hover over the given HTML table row.
As for the similar threads feature, it's actually a default feature of vBulletin, the forum system which powers DaniWeb. ( www.vbulletin.com for more information)
cscgal
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