Problem 55

To solve, convert the parabola $$y= \frac {1}{4}x^{2}$$ into the standard equation form: $x^2=4y$.
Therefore, the parabola opens upwards, satisfying $2p=4$.
Since $$\frac {p}{2}=1$$, the focus is at (0, $$\frac {p}{2}$$).
Thus, the coordinates of the parabola's focus are (0, 1).
Furthermore, the equation of the directrix of the parabola is $y=-\frac {p}{2}$, that is, $y=-1$.
Therefore, the distance $d$ between the focus and the directrix of the parabola is $d=1-(-1)=2$.
Hence, the answer is: $\boxed{2}$.
First, convert $$y= \frac {1}{4}x^{2}$$ into the standard equation of an upward-opening parabola, obtaining the coefficient $2p=4$. Then, using the formula, we find the focus coordinates to be (0, 1), and the directrix equation to be $y=-1$. Finally, we can determine the distance from the focus to the directrix of the parabola.
This question uses the parabola of a quadratic function graph as an example, focusing on the basic concepts of the parabola's focus and directrix, and is considered a basic question.