Rhino can open/import such files directly, provided they're formatted correctly (select the 'points' file type, which includes .txt, in the open/import dialog). What you posted needs a little cleaning; I pasted it into
Notepad2 and hit ALT+Z (remove the first character of each line) four times to remove the line numbers, so it appeared like this:
Code:
676157.097 215008.186 441.894 20
676157.078 215003.138 441.699 28
676157.047 215000.309 441.634 28
676157.127 215001.707 441.750 29
676157.087 214995.238 441.524 20
676157.656 214993.247 441.559 20
676157.891 214989.092 441.609 28
676157.196 214988.867 441.560 28
This imported into Rhino as a point cloud, using space as the delimiter in the import options dialog. Apparently Rhino was able to deal with the multiple spaces between the Y and Z coordinates, and was also able to ignore the two-digit number at the end of each line. Note that it will fail if there are lines which cannot be parsed, so check the top of the file and make sure there isn't any unnecessary information there; every line in the file should look like the ones above.