The build version of BO XI Enterprise can be obtained from the Settings area of the CMC. Build version of individual services can be obtained from the CCM. For client tools (Designer, DeskI, etc.), right click on the executables (BusObj.exe, Designer.exe, etc.) and choose Properties → Versions. (For a Windows installation, the executables are installed at the following path: \win32_x86).
Versions of SPs and FPs for Crystal Reports 2008 can be found here: http://wiki.sdn.sap.com/wiki/display/BOBJ/Crystal+Reports+2008+-+Version+and+Download+information+for+SPs+and+FPs
For XI 3.x line, see also SAP Note: 1287906
For SAP BI BusOjects 4.x, see SAP Note: 1602088
This SCN blog post can be helpful too:
SAP BI BusinessObjects 4.0
Product version:
XI 4.0 and Build: 565 → SAP BI BusObjects 4.0 SP02 Patch 12
version 14.04 and Build 738 → SAP BI BusObjects 4.0 SP4 no patch
version 14.04 and Build 855 → SAP BI BusObjects 4.0 SP4 Patch 5
BO XI 3.1 SP6
12.6.0.1596 → XI 3.1 SP6
BO XI 3.1 SP5
12.5.0.1190 → XI 3.1 SP5
12.5.3.1475 → XI 3.1 SP5 FP3
12.5.4.1599 → XI 3.1 SP5 FP4
12.5.4.1600 → XI 3.1 SP5 special fix (for a customer the c3_calc.dll)
12.5.5.1710 → XI 3.1 SP5 FP5
BO XI 3.1 SP4
12.4.0.966 → XI 3.1 SP4
12.4.1.1188 → XI 3.1 SP4 + FP 4.1
BO XI 3.1 SP3
12.3.0.601 → XI 3.1 SP3
12.3.1.684 → XI 3.1 + SP3 + FP3.1
12.3.2.753 → XI 3.1 + SP3 + FP3.2
12.3.3.812 → XI 3.1 + SP3 + FP3.3
12.3.4.895 → XI 3.1 + SP3 + FP3.4
12.3.5.925 → XI 3.1 + SP3 + FP3.5
12.3.6.1006 → XI 3.1 + SP3 + FP3.6
BO XI 3.1 SP2
12.2.0.290 → XI 3.1 + SP2
12.2.1.412 → XI 3.1 + SP2 + FP2.1
12.2.2.441 or 12.2.2.453 → XI 3.1 + SP2 + FP2.2
12.2.3.467 → XI 3.1 + SP2 + FP2.3
12.2.4.507 → XI 3.1 + SP2 + FP2.4
12.2.5.537 → XI 3.1 + SP2 + FP2.5
12.2.6.567 → XI 3.1 + SP2 + FP2.6
12.2.7.598 → XI 3.1 + SP2 + FP2.7
12.2.8.638 → XI 3.1 + SP2 + FP2.8
12.2.9.698 → XI 3.1 + SP2 + FP2.9
12.2.10.810 → XI 3.1 + SP2 + FP2.10
BO XI 3.1
12.1.0.882 → XI 3.1
12.1.1.957 → FP1.1
12.1.2.996 → FP1.2
12.1.3.1028 → FP1.3
12.1.4.1068 → FP1.4
12.1.5.1096 → FP1.5
12.1.6.1116 → FP1.6
12.1.7.1144 → FP1.7
12.1.8.1176 → FP1.8
12.1.9.1290 → FP1.9
12.1.10.1390 → FP1.10
12.1.11.1454 → FP1.11
BO XI 3.0
12.0.0.683.BOE_Titan_RTM → XI 3.0
12.0.0.796.BOE_Titan_FP_RTM_REL → FP 1
12.0.0.840.BOE_Titan_FP_RTM_REL → FP 2
12.0.3.900 BOE_Titan_FP_RTM_REL → FP 3
BO XI r2
11.5.0.313 → RTM
11.5.3.417 → SP1
11.5.7.608 → MHF1
11.5.7.682 → CHF13
11.5.7.723 → CHF14
11.5.7.770 → CHF15
11.5.7.811 → CHF16
11.5.7.852 → CHF17
11.5.7.1048 → CHF20
11.5.8.826 → SP2
11.5.8.826 → FP2.1
11.5.8.939 → FP2.2
11.5.8.963 → FP2.3
11.5.8.998 → FP2.4
11.5.8.1030 → FP2.5
11.5.8.1061 → FP2.6
11.5.8.1111 → FP2.7
11.5.8.1187 → FP2.8
11.5.8.1237 → FP2.9
11.5.9.1076 → SP3
11.5.9.1101 → FP3.1
11.5.9.1138 → FP3.2
11.5.9.1176 → FP3.3
11.5.9.1202 → FP3.4
11.5.9.1227 → FP3.5
11.5.9.1265 → FP3.6
11.5.9.1330 → FP3.7
11.5.9.1378 → FP3.8
11.5.9.1449 → FP3.9
11.5.10.1263 → SP4
11.5.10.1298 → FP4.1
11.5.10.1322 → FP4.2
11.5.10.1358 → FP4.3
11.5.10.1404 → FP4.4
11.5.10.1426 → FP4.5
11.5.10.1460 → FP4.6
11.5.10.1491 → FP4.7
11.5.10.1554 → FP4.8
11.5.10.1619 → FP4.9
11.5.10.1681 → FP4.10
11.5.10.1765 → FP4.11
11.5.10.1854 → FP4.12
11.5.11.1470 → SP5
11.5.11.1545 → FP 5.1
11.5.11.1578 → FP 5.2
11.5.11.1610 → FP 5.3
11.5.11.1639 → FP 5.4
11.5.11.1673 → FP 5.5
11.5.11.1732 → FP 5.6
11.5.11.1797 → FP 5.7
11.5.11.1856 → FP 5.8
11.5.12.1838 → SP6
RTM = Release To Market (first release, without any patches).
MHF = Monthly Hot Fix.
CHF = Critical Hot Fix.
SP = Service Pack.
FP = Fix Pack.
Updated by Andreas for SAP BI 4.0
Marek Chladny 
(BOB member since 2003-11-27)