This function behaves similarly to MATLAB's GINPUT, with an added ability to customize the cursor color, line width, and line style. From the function HELP:
[X,Y] = ginputc(N) gets N points from the current axes and returns the X- and Y-coordinates in length N vectors X and Y. The cursor can be positioned using a mouse. Data points are entered by pressing a mouse button or any key on the keyboard except carriage return, which terminates the input before N points are entered. Note: if there are multiple axes in the figure, use mouse clicks instead of key presses. Key presses may not select the axes where the cursor is.

[X,Y] = ginputc gathers an unlimited number of points until the return key is pressed.

[X,Y] = ginputc(N, PARAM, VALUE) and [X,Y] = ginputc(PARAM, VALUE) specifies additional parameters for customizing. Valid values for PARAM are:
'Color' : A three-element RGB vector, or one of the MATLAB predefined names, specifying the line color. See the ColorSpec reference page for more information on specifying color. Default is 'k' (black).
'LineWidth' : A scalar number specifying the line width. Default is 0.5.
'LineStyle' : '-', '--', '-.', ':'. Default is '-'.
'ShowPoints' : TRUE or FALSE specifying whether to show the points being selected. Default is false.
'ConnectPoints' : TRUE or FALSE specifying whether to connect the points as they are being selected. This only applies when 'ShowPoints' is set to TRUE. Default is true.

[X,Y,BUTTON] = ginputc(...) returns a third result, BUTTON, that contains a vector of integers specifying which mouse button was used (1,2,3 from left) or ASCII numbers if a key on the keyboard was used.

[X,Y,BUTTON,AX] = ginputc(...) returns a fourth result, AX, that contains a vector of axes handles for the data points collected.

Examples:
[x, y] = ginputc;

[x, y] = ginputc(5, 'Color', 'r', 'LineWidth', 3);

[x, y, button] = ginputc(1, 'LineStyle', ':');

subplot(1, 2, 1); subplot(1, 2, 2);
[x, y, button, ax] = ginputc;

[x, y] = ginputc('ShowPoints', true, 'ConnectPoints', true);