I got tired of typing add-pssnapin blah, especially with Quest's AD snap-in's longer than usual name so I came up with a little script that enumerates registered snap-ins, and lists a simple numbered menu showing those that are not already loaded into memory. You just type the number and hit enter to load it. Enter on an empty line exits the script. Yeah, it's brain-dead, but hey, I think I was brain-dead to continually type long commands in every single session to load stuff  

UPDATE 2007-08-16: I was even more braindead than I realised - I copied up a broken version without the $notloaded array. Ooops. Fixed.

1. write-progress "Enumerating Snapins" "Registered..."
2. $snaps = get-pssnapin -r
3.  
4. write-progress "Enumerating Snapins" "Loaded..."
5. $loaded = get-pssnapin | % {$_.name}
6. $notloaded  = @()
7.  
8. write-progress "Enumerating Snapins" "Complete." -Completed # glitchy
9.  
10. $i = 0; "";
11.  
12. foreach ($snap in $snaps) {
13.         if (-not($loaded -contains $snap.name)) {
14.                 Write-Host -fore cyan -nonewline "${i}) "
15.                 write-host -fore green $snap.name
16.                     $notloaded  += $snap
17.                 $i++
18.         }
19. }
20.  
21. if ($i -eq 0) {
22.         Write-Warning "Any eligible snapins are already loaded."
23.         exit;
24. }
25.  
26. $i--;
27. Write-Host -fore yellow "<enter> to quit"
28.  
29. do {
30.         write-host -nonewline "Load 0 - ${i}: ";
31.         $choice = [console]::readline()
32.         if ($choice -and ($choice -lt 0) -or ($choice -gt $i)) {
33.                 Write-Warning "'${choice}' is out of range!"
34.                 continue;
35.         }
36.         if ($choice) {
37.                 "loading $($notloaded[$choice].name) ..."
38.                 add-pssnapin $notloaded[$choice]
39.         }
40. } while ($choice)

Just pop it into a function or a ps1 script.

You'll notice how when this is run from a clear screen, the progress bar disappears, then suddenly reappears and the first few menu items are hidden. This is a bug in the powershell.exe host. Vote on it here:

https://connect.microsoft.com/feedback/ViewFeedback.aspx?FeedbackID=291380&SiteID=99