Only two months left in this year. Which may mean the accumulation of deadlines or the coming of your season's festivities. As always, the Wiki is a reliable source of information on Tcl and Tk.
Software updates
The famous interface to Windows system functions has reached a new version - check out version 4.3.8 of TWAPI.
One application of TWAPI allows you to automate all manner of well-known "office" programs, such as MS Excel but also Google Earth: one package to rule them all, under the inconspicous name CAWT.
If you are dealing with JSON, then you be interested in the JSON value extraction benchmark. As there are a lot of libraries out there, choosing the one that is right for your applications is a tricky process. Do not expect an absolute answer.
Some widgets simply do not fit on a single screen and require some form of scrolling. Try Scrollutil to make your life easy, when you run into that!
Tcl exists in a variety of implementations. For the Windows platform, read ".NET", you might benefit from Eagle, as that works seamlessly with said platform. To get some feeling for it, perhaps join the Eagle sandbox Contest?
New (?) kids on the block
Let's discuss climate change and other world-wide problems in a different context. The OpenSky App does not judge, it simply shows the flights of planes that you select.
A beautiful cartoon-like picture appeared this month on the Wiki: a head of a tiger, illustrating the capabilities of the Blend2d library.
Arduinos are those nifty little gadgets that can do all manner of remarkable things. At least, if you tell them how to do it. Firmata may help you use Tcl for this conversation.
Widgets, snidgets and other graphics
A listbox able to show multilne entries, check out the tlistbox package.
Clocks need not be round with two hands, nor the digital gadgets of long ago. The Tk Dali Clock is a playful variation, no sudden change in the digits, but a smooth morphing.
Cloning a Gnocl Widget Made Simple? By the looks of the code, it is indeed really simple.
Dive into details
Abstract Data Types, who does not know them? This page discusses them at some length - for a rainy sunday afternoon, perhaps?
The mysteries of character encodings unravelled ... Perhaps save that one for a rainy evening.
Probably every programmer has to do this at some point: examine the contents of a recursive structure, say, of directories. Such Directory recursion can be done in many different ways. For the puzzlers.
The Wiki is not known as a source of information on the animal kingdom. So, not surprisingly, duck typing is only superficially about waterfowl.