The clock at the Train Station shows the time from your computer's internal clock.
Using the fishing rod at the end of Act One or the very beginning of Act two on the Oasis. You have to have attached the horse hair to the whip; but not the hook and bait.
It can result in Al catching one of two funny items. Sometimes you get one, sometimes the other...you sometimes even get both; sometimes it doesn't work.
Al must be at the Oasis for this one; after creating the fishing pole, attach the barrel-cactus needle to the line; then add the worm. Al says a funny line. (Doesn't always happen; I suspect a random trigger set when you begin a new game.)
(My favorite) - While at the Train Station, use the talk icon on the lamppost.
Al sings "Singin' in the Rain." ("Waitin' fer the Train.")
"Talk" to the clock at the station.
While in the Sheriff's Office, use the talk icon on his wastebasket.
Patooey!
At the Saguaro cactus area, click the "talk" icon on the sky!
Al sings a line from "Oklahoma" (First Act only)
Also in the same location, click on the big rocks.
Al sings a rock song.
When picking the Prickly pear, observe the dead horse at the bottom of the gulch. Use the Talk Icon on the horse. Al sings the theme song from an old TV show, Mr. Ed.
Whilst talking to Lou about a job, use the hand icon on his desk.
The room transforms.
In the Chief's tent, click the
talk icon on the Al Emmo game behind where Al is sitting.
Then click the hand icon twice,
and pick up the CD. Use the CD on the computer. and you will
start to play Al Emmo and the Lost Dutchman's Mine. You can
continue as long as you want; even up to the point where you are
in the Chief's tent and want to play another "game within a
game within a game." If you got into such a game and want to
exit, use the "Quit" option to return to the 'real'
game.
At the Gorge: Talk to the Gorge several times to hear the "echo" (Thanks Shigeru, for finding this one.)
After collecting wood shavings for the termites, and before you blow down the tree, use the knife again on the dead tree.
Al carves a love-sign.
In Koko's, look at the barrel in the foreground, then use the hand icon to take a "small sip."
Al passes out. Try it again, and he declines.
While inside the Post Office, 'talk' to the outgoing mail slot.
He makes a rude noise into the slot.
Just a one-liner - outside the Post Office, click the talk icon on the Post office sign.
"You've Got Mail!"
There are DOZENS of one-liners strewn throughout the game.