In the meantime, here is one from my "Missing List" from earlier in the season, Hisanori Takahashi.
Takahashi signed as free agent prior to the season and was traded to the Colorado Rockies for a player to be named later on June 22. He was in Triple-A Iowa at the time after pitching just 3 innings in 3 appearances for the Cubs in early April. Takahashi remains at the AAA level, pitching for the Colorado Springs Sky Sox and even stayed in the same league (Pacific Coast) as Iowa.
Surprisingly, other former Cubs currently donning the Sky Sox uniform include Justin Berg, Chris Volstad, Xavier Nady and manager Glenallen Hill. Tyler Colvin, Manny Corpas and DJ LeMahieu also started the season there but have since been called up.
As I note on the 2013 Cubs Custom Team Set page, the Cubs have now used 41 different players since Opening Day. Last year's team record of 53 is well within reach, especially with the Cubs being sellers at the deadline.And the fact that it is not even the All-Star break yet and there will still be a smattering of September call-ups.