Here is Metroid Classic, a remake of the original Metroid.
The game use Allegro 4 and is not ressource hungry.
Note that this game is not 100% finished, so some features may be missing (GameOver screen is a little crude for example).
There is a cfg file in appdata (SMTC.cfg) where you can try to play with a few parameter, like gameversion (initialy at 1, but 2 should work) or the cvar.megaman_mode that change the graphics. But, I have not tested any of this, so it may just Segfault...
Keys are
DPad : move
{X} : Jump
{B} : Fire
{Y} : Change weapon
History log
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Build 03
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* Fixed Acid
* Fixed a bug when dying out of the screen
29/11/2013 03:54 UTC
v1.0.0.01