Apple

2.5GHz Mac mini

2.5GHz Dual-core
Intel Core i5 processor
4GB RAM 
500GB HDD
Intel HD Graphics 4000

Special order (2-3 weeks)
MD387LL/A 

2.3GHz Mac mini

2.3GHz Quad-core
Intel Core i7 processor
4GB RAM
1TB HDD
Intel Graphics 4000

Special Order (2-3 weeks)
MD388LL/A 

Mac mini with OS X Server

2.3GHz Quad-core
Intel Core i7 Processor
4GB RAM
2x 1TB HDD
Intel HD Graphics 4000

McGill Computer Store has in-stock desktops available ready to go. Other variations on the in-stock configurations are also available, with a longer delay.  

Desktops

21.5" iMac

MD093LL/A - $1249