The first is a personal favorite of mine.
Game about a Soup Factory (Click to Download the Trial)
I actually reviewed this game earlier in the year, I later found out that the game is a Zoop clone. After trying Soup Factory again I still enjoyed it. The game ramps up the difficulty pretty quick and if you can actually make it past the 8 minute mark, which is the length of time we are allowed to play indie game trials, then you are quite better at the game than me.
Next up we have,
Crystal Spear Remake (Click to Download the Trial)
This is quite a simple game and right before I decided to toss the game into the trash bin, the gameplay emerged. All required of you is a simple press of the left trigger and slight movements of the thumbstick. Your goal, to maneuver through the boxes while dodging the crystal spears. The trigger is an accelerant, and I have yet to discover the top speed. Dodging the spears at high rates of speed will force a zen like connection to your controller and the screen. There are other buttons, but there is no need to use them. The game saves your fastest times through the spears, and you should be able to get a few runs in before the 8 minute timer appears, forcing you to restart the game.
Another Tetris Clone? Not so!
Pentominon (Click to Download the Trial)
The intro screen tells us that the main goal is not to make lines but to create ignition. I've been playing the game for a good couple of hours and I've created ignition once. Either I am horrible at the game or its ridiculously hard. My one ignition caused me such a joy though. Pentominon, like Crystal Spear above is good for inducing the trance like state of gaming that I so thoroughly enjoy. Music plays an integral part of this game. It is hard to describe in words, but by configuring the blocks on the screen you are able to create music. The trial game allows you to experience a good portion of the game, enough to keep you entertained. Purchasing enables free matrix placement of the music blocks and I have definitely been considering purchasing this one.
And last but not least,
Lines, or pipes in the popular parlance should be familiar to most gamers. But just in case its not, a description of the gameplay. You are given squares in the tetris style, each of which is overlaid with a line segment in various configurations. Simply make a line by connecting squares with adjoining line segments. Making a line segment spanning 5 squares or more scores you points and you are limited to a three minute game in the trial but I played this one over and over. Purchasing enables endless mode but might I suggest creating this type of game yourself?
That's all for now, I am sure there are quite a few more games with an enjoyable replayable trial mode and I might add to this list in the future, If you know of any please let me know and I will add them.