diff --git a/main.cpp b/main.cpp
index 7b553c1..17b5b7b 100644
--- a/main.cpp
+++ b/main.cpp
@@ -33,6 +33,7 @@ float speed = 0.0f;
 float max_speed = 200.0f;
 
 float rspeed = 200.0f;
+float bobbing = 0.0f;
 
 float dt;
 
@@ -318,6 +319,9 @@ int main(int argc, char *argv[])
         dt = float(SDL_GetTicks() - millis)/1000.0f;
         millis = SDL_GetTicks();
 
+        bobbing += dt*1000.0f;
+        height = 32 + SDL_sinf(bobbing*DEG_TO_RAD)*(speed/100.0f);
+
         while (SDL_PollEvent(&e))
         {
             if (e.type==SDL_EVENT_QUIT) { should_exit=true; break; }