Since in the z80 calculators there aren't folders unless you use some shell like DoorsCS, I prefix the name of my TI-BASIC programs for easier access.

Here are my prefixes:
A - easy access to execute because they appear first in the programs listing
G - game under development
R - reusable subroutine in a program (generally to Rcl them in a program)
N - notes or nifty programs
U - utilities
T - tools (meh, ends to be the same as utilities)
Z - list in the end of the program list but before Theta. For data programs or subroutines of large programs (games mostly)
Theta - list in the end of the program list

About general organization of programs I always keep a A, A1, A2, A3 programs for experimenting TI-BASIC code and optimization of parts of code.
About groups, I keep backup copies prefixed with CS and suffixed with a number (suggestion from here in the forums).

Now it is your turn.

I only prefix them for easy access. For programs I'm currently working with, they either start with A or theta followed by their name for quick access when I want to edit them.

About general organization of programs I always keep a A, A1, A2, A3 programs for experimenting TI-BASIC code and optimization of parts of code.

I also do this all the time when I'm experimenting or working with things.

I generally keep all my prog names as short as I can to save space. I'll usually prefix them with my game acronyms, or something close. Example, Illusiat 13 prefix is I13

In some cases, I tend to call the main launcher prgmA, though

Some people also use Theta. I used it in Mana Force series.

I discourage the usage of Theta in variable and program names now, though, because in some cases it's a major PITA to transfer from computer to emulators or from computer to calcs

I never used theta cause I have some 300 programs and it takes forever to got to the bottom.  (Even with pressing up at the top.)

Anyway, I Used to use A in front of everything, but then I ended up with about 150 programs starting with A.

I backed up my calc a month ago and it took about 30 mins.

A: any program I'm working on, generally i only have one project at once and other projects are grouped and ungrouped whenever I feel like working on them

Everything else doesn't have a prefix since basically the only time I'm using the PRGM menu is when testing/editing programs. Games are all hidden and accessed from MOS, and fontsets and 16lvl pictures are accessed from Zstart's menu. Those are pretty much the only programs that I have in mem at once:P (math progs are ungrouped whenever i need them (like SATs) and everything else gets grouped then deleted

Since pokemon is such a large project, I make sure everything else starts with a 'Z' to make sure pokemon is highest up on the list, for easier starting.